Well, for starters, this post is written using Dragon naturally speaking, which in theory will only use words (including proper nouns) which it considers to be correct in either British or American English.
Rightly or wrongly, as far as Dragon is concerned, Legos is a correct term, and of course it’s widely used across North America. Since Dragon will not accept popular mis-spellings, this makes Legos absolutely valid in terms of “common” usage. However, usage alone doesn’t make a term correct
If the plural is acceptable in American English, but it’s never used in British English, is the American English usage simply acceptable because American English often tends to be a lot more logical, and in this sense, if you can have one Lego, i.e. a single brick, then building any kind of structure out of 2 or more Lego bricks would indeed mean that you are using Legos, are you not?
Except of course that this question should be about British or American English usage, but about the usage of a product which might have British origins, but which is ultimately Danish. Lego is a contraction of a Danish phrase leg godt meaning “play well”.
Logically speaking, you cannot have “play wells” in the plural – the name quite logically implies that the act of playing has to involve multiple bricks, because a single brick wouldn’t be anything worth playing with.
The whole beauty of Lego is not so much that you might have a single much loved brick or toy to play with (for that, there are plenty of other toy or model manufacturers like Corgi or Dinky cars or Hornby trains), but that the process of playing or creating is constant and ongoing.
Therefore, even if as a British English speaker I might know perfectly well what an American English speaker means when they talk of Legos, it isn’t really a correct usage. Furthermore, it is actually relegating Lego to the same status as any other toy, and no fanatic can accept that!
Since @plasticplanners has been set up to use Lego in a creative fashion to educate immature adults, it is a distinction we think is worth making from time to time.
On the other hand, we really don’t need to get that beat up about this – if a pile of plastic bricks can be used to create anything, does it really matter if language is twisted around a bit and used slightly incorrectly? I don’t think it’s really all that important, but I would like to think that if I was actually writing this article on the other side of the pond, that I would still use the correct term Lego.
On a similar note, this account has been set up as the “plastic planners” – not “Lego transport” or anything similar, because this is an entirely unofficial fan website, and it’s got absolutely nothing to do with the Lego group, or any of their trademarks.