Who, which, that

The local public radio station receives support from a mattress company. They acknowledge this support by saying something like " . . . the mattress company that provides . . .."  However, the copy writers must be crossing out each others edits behind the scenes, because the "that" in the acknowledgment comes out sometimes as "who" and sometimes as "which."

I often hear people refer to companies as "who."  Perhaps it's British. I don't know. It seems wrong to me.

Using "which" here is definitely more British than American. The rule most tech writers insist on and most Americans use instinctively is the one the Fowlers put forth in The King's English more than a century ago. They said

'That' is evidently regarded by most writers as nothing more than an ornamental variation for 'who' and 'which,' to be used, not indeed immoderately, but quite without discrimination. The opinion is excusable; it is not easy to draw any distinction that is at all consistently supported by usage. There was formerly a tendency to use 'that' for everything: the tendency now is to use 'who' and 'which' for everything. 

. . .

This confusion is to be regretted; for although no distinction can be  authoritatively drawn between the two relatives, an obvious one presents itself. The few limitations on 'that' and 'who' about which everyone is agreed all point to 'that' as the defining relative, 'who' or 'which' as the non-defining.

They go on to provide many examples, but they've already said enough.

Kennedy

On Friday, November 22, 1963, President John F Kennedy was assassinated in Dallas, Texas. For many years afterward, I could not hear the date November 22 without powerful memories.  Twelve years ago November 22 was again a Friday, and that morning I was sitting in an eleventh floor conference room at Oracle's headquarters in Redwood Shores. Looking out at the dark, threatening sky, I felt strangely apprehensive, but none of the young techies around me knew the significance of the date.

Elude vs allude

I never saw this one before. A technical communicator posted to a list: ". . . you eluded to the possibility of . . .."

She meant "alluded." Allude = refer indirectly to.  Elude = avoid by clever maneuvering.

Also, if you don't understand a subtle point, you might say that it eludes you.