lucy24 - 10:04 am on Aug 10, 2011 (gmt 0)
Historically, no. Two of the most striking distinctions between British and American English-- the treatment of postvocalic "r" * and the pronunciation shift of short "a"-- are British innovations that occured after the dialects split. So American English is phonetically more conservative. (The same applies to several differences between Latin American and European Spanish.)
Most rules of spelling and punctuation did not became standardized until long after the dialects diverged. Like, er, standardize vs. -ise. A lot of things you think of as being carved in stone didn't take on their current form until late in the 19th century.
And that's not even getting into the differing terminology for things that didn't exist in 1507 or 1620 or 1783 or whatever you're setting as your cutoff.
Use the English dialect you're comfortable with and that you're most likely to write correctly within its own rules.
* In, ahem, English English. As opposed to, say, for example, Scots English.