Without wanting to do the appeal to authority thing too much, as someone who's British born and bred, a CAMRA member, worked in pubs & at cask festivals, and judged in the lower reaches of the Champion Beer of Britain - I can agree with some of that and would bitterly (sic) disagree with some of it, in particular :
5. Virtually every beer called "bitter" in the UK is between 3.2 and 4.8% ABV. Stronger than that is extremely uncommon -- and only breweries that market a lot to the US market even make them, as far as I know.
That's where the tourist view doesn't reflect reality. Yes stronger than that is extremely uncommon on the handpulls of a typical pub - although you do see them, more down south and in city centres - but just about every cask-led brewery I can think of makes them. But often they only brew them once a year, not for pubs but as a Christmas special, or for the festival season. One model is to brew in say August so a few casks get released for all the beer festivals in September-October, and then bottle the rest for the Christmas season (Fuller's Vintage sort of fits this model, mostly sold at Christmas in bottle but they do have eg a cask or two at GBBF), or just to have in bottles to add a bit of glamour year-round to the fridges of tied pubs.
2. The BJCP guidelines have gotten way better than they used to be, but they still aren't super precise on these styles
3. There is a wider variety in bitters than most people think. Some are quite dark, even (~14 SRM) and they vary a lot in malt/hop balance, despite what the guidelines state...
4. Tons of them utilize US hops and have for decades, while some of them exclusively use traditional British hops - very few use a "boatload" of earthy British hops. The bitters that are really hoppy and hop-forward are almost always hoppy in a relatable way to US beers (fruity/floral/piney/Citrusy) regardless of the hops used, so don't think you need to be using a pound of fuggles. Dry hopping with a half ounce of EKG is perfectly appropriate, but so is dry-hopping with an ounce of Amarillo or not dry-hopping or using flameout/whirlpool hops at all. One note -- hop bills are usually somewhat simple and you won't see the same sort of 6-hop blends used for aroma in a bitter that you have come to expect from an APA or IPA.
2 and 3 are certainly true, and the organic growth of European beer makes it resistant to fitting into neat categories, on the other hand if you're paying any attention to "guidelines" it implies you're looking to competitions, in which case you're probably wise to aim for the midpoint of the guidelines. But one thing that really muddies the water is the regional variations in British beer, which few foreigners seem to understand - the typical tourist haunts of London and the Thames valley are not particularly representative of beer in the rest of the country, but may explain why USians think British styles should have weirdly high amounts of crystal in them. It's not quite the same, but would one consider going to New York a sufficient grounding in US beer culture, or would one learn more going to Portland?
Talking about this stuff isn't helped by the fact that the word "bitter" means different things to different people. To lager drinkers, "bitter" is "anything from a handpull". To the average cask drinker, "bitter" is generally taken to mean either session bitter (3.6-4%) or best (4.1-4.5%) made with traditional British/European hops. To geeks, it probably makes sense to categorise further.
Obviously there's a grey area, but I'd broadly disagree with 4) in that <4.5% cask beers that are obviously New-World-hoppy aren't really considered as "bitter" as such by the people who drink them, even if nobody's quite worked out what to call them yet. "Pale ale" gets used but is one of those terms that has a multiplicity of meanings already. There's a definite group of "golden bests" - typically with little or no crystal, fairly high BU:GU, 4-4.5% ABV, New World hops - often New Zealand. I guess in evolutionary terms they are to bitter what West Coast IPAs are to SNPA. And they've spawned "cask hazies" - typically a bit weaker but using some of the techniques of NEIPAs to compensate for the lack of body from alcohol. Jeff Alworth talks about them here
And then there's all the stronger stuff. The average drinker would only regularly know one or two by name produced by their local regional brewery/ies, but not really think of them as a "style". And since they don't have quite so much commercial pressure on them as the session beers, they tend to be more varied. So I'd suggest it's useful to retain the idea of "strong bitter" as a dumping ground for all the strong stuff that exists, but at the same time it isn't necessarily a very useful concept for directing the creation of new beers. You can also carve out things like the "traditional" golden ales like Exmoor Gold and Summer Lightning - 5%, pale, English hops - you only really seem to see them down south, and I know of a commercial one that's been reformulated to take it below the 4.5% cask norm, suspect it won't be the last.
7. "ESB" is a beer invented by Fuller's for the US market. It's a really good beer and its success is not unwarranted, and British people love it too. But it is as far removed from the "bitter" style in England as most American Pale Ales are -- truly the exception that proves the rule. Personally, I think Fuller's ESB is a better example of an American Amber Ale than it is of a British Bitter, even though there is essentially an entire BJCP subcategory (Strong Bitters) build around the success of Fuller's ESB.
Fuller's replaced their Old Burton Ale with a new seasonal beer, Winter Ale, in 1969. It was relabelled as ESB in 1971 and made a core beer, AIUI it only really took off in the US in the late 70s. I wouldn't say it's too removed from bitter, given that it's literally brewed with the same wort as London Pride and Chiswick Bitter! Most of the strong stuff has a different balance to a best and it's typical in that regard, and it's not so different to other southern beers like Bishop's Finger etc. As an aside, Jeff wrote a nice piece about ESB
the other day.
As per above - it serves a purpose to have a grouping for the strong stuff, even if Fuller's ESB is maybe a little way from the midpoint of that group (qv Zum Uerig and alts)
1. British Bitters are meant for cask, not tap nor bottle. They will never taste "just right" if you're bottling or kegging them with CO2 or beer gas. The best you can do is to not overcarbonate -- reduce the CO2 level compared to your other beers or bottle condition with less sugar, or keg with beer gas, if you are able. I think 3 oz of dextrose per 5 gallon batch is the high end of what you should do in terms of bottle conditioning.
Again this is an area where it feels that US practice is too heavily influenced by experience in tourist traps with dead beer in southern England. Really great cask beer should be bursting with condition - and then there's the whole sparkler debate. I'd agree it's really hard to get the carbonation right with external CO2 though, and kegging in general really doesn't suit them, but I'd probably go a little higher than your target as my norm for bottle conditioning to get it "right" in the glass. Maybe 2g of sucrose in a 500ml bottle, 1.7g in a 330ml (they don't scale linearly)? So if I get the sums right, that's the equivalent of 2.6-3.4oz per 5 US gallons depending on bottle size. It is hard to get right, you just know when it is.
8. Most of the British Ales available in bottled form in the US are atypical examples. Hobgoblin, ESB, Old Peculiar, Old Speckled Hen, Sam Smith's, St. Peter's, Young's London Ale are all atypical examples. You are unlikely to get a "true" example of the style in the US except at a very small number of specialty bars that manage to import casks of the real deal. Unless you live somewhere really hip like NYC, you will probably have to travel to the UK to taste real British cask ale properly. Some of the bottled versions of these styles are pretty decent, but getting them fresh and unpasteurized can be challenging.
Hmm - well all the specific beers you mention are >=5% in bottle, so are a different kettle of fish to mainstream bitter, although some of them drop down to 4.5% in cask form. It's common for bottle versions to be stronger than cask - Old PeculiE
r is the only one that is the same in both formats, Young's Special is perhaps the most extreme at 4.5% cask, 6.4% bottle (I assume that's what you're referring to as London Ale? Export names can be confusing). But the bottle versions of the ones you mention are :
Hobgoblin 5.2% (another one where the cask has come down to 4.5% from much higher)
ESB 5.9% (5.5% cask)
Old Peculier 5.6%
Hen 5% (4.5% cask)
Sam's - OBB is their only regular cask option at 4%, with no bottle equivalent AFAIK
So I'd say that diversity is pretty typical for strong bitters - but your list is clearly geared to US ideas on strength and is pretty irrelevant to any discussion of "normal" bitters.
And just generally I get the impression that what you see over there is slanted towards southern breweries which reinforces the idea that all British beers are crystal-sweet, it's like thinking all wine must be like blush Zinfandel just because one hasn't encountered Chablis. It doesn't help that it tends to be the bigger breweries or those that are part of multinationals that have the resources to export effectively, and they tend to be the ones producing the less interesting beer.