...Is there a definition out there for classic American malt liquor?
It's such a weird category, and the name 'Malt Liquor' is apparently only a result of antiquated post prohibition (often on a local level) alcohol laws, so it probably shouldn't even be recognized as it's own "style" (like a lot of other categories too...but that's for another thread
).
I guess it has come to mean high alcohol beer regardless of the fermentation method (with the ghetto beers pretty universally having a very high adjunct-to-malt ratio as well).
But really, with beers like Optimator, Oktoberfest, and other more
real "styles" being labeled as 'malt liquor' in some jurisdictions, I personally feel it makes the term pretty useless in general.
I'd just call it a strong lager...that's what it is before you dilute it, and that name covers it better than anything else.
As far as "to dilute, or not to dilute" (from the lost version of Hamlet, no?) that's a decision only
you can make...and it depends entirely on what you want to drink.
As for me, I'd leave it alone.