> but you should be aware that you are not using that term the way anyone else uses it.

Most people (including, typically, the companies actually manufacturing and selling blades and enclosures) would also in this context reasonably infer "2U or 4U blade" to be referring to a (partially-or-fully-)filled enclosure, rather than pedantically assume that someone (who is implied to own and use such a server) doesn't know the difference between a blade and a pizza box - but given that we've already deviated from using terms the way anyone else uses them, what's one more deviation, right? :)