Well, what did Graham Wheeler's book say? Don't keep us in suspense.
If you read his book, you will see that most of the recipes do not contain sizable amounts of crystal malt. In fact, a large number of the recipes contain no crystal malt. The darker colors that we associate with British bitter are often the result of the addition of a small amount of black or chocolate malt.
Is it the CAMRA publication for homebrewers or another book?
I was remarking the other day to a friend who travels frequently to Europe - I have never had a fresh example of many of the beers I brew and I wonder how well the recipes I brew stack up to the real thing. For example I recently brewed a Mild from the Craft beers for the Homebrewer from Cigar City Brewing - it is fantastic, but I wish I had access to a British version to see how well it compares...I don't even have access to the Cigar City version!
Real Ales like Fullers are much better at the source.
S. cerevvisiae has it right, there is not large amounts of crystal in most of the recipes in Wheeler's books or in the Real Ale Almanac by Protz. Many are just Pale Ale malt in the grain bill. Some will have a little crystal and brewer's invert sugar, maybe some torrified wheat.
I have been reducing my pitch rate on the Bitters I brew, as they were too clean of esters. Reducing aeration also helped. One local brewpub that makes some fairly fruity English style beers will double the pitch rate to make a fairly clean American style ale.
Chris White was at the LHBS Big Brew last year. I asked about pitch rates for British style beers and he said the British brewers underpitch and get more esters. The last few Bitters I brewed have had the pitch rate reduced to around a half, next time I will try the 1/3 that S. c. recommends.