DB is getting married in a week or so, and he sent me a message asking me if I'd ask my DH to be an usher! (ignore the fact that this should ahv ebeen aranged months ago) Now I haven't replied yet because I feel that I shouldn't be the one asking DH. DB never actually picks up a phone to tlak, all communication with him is done via facebook or mobile - mainly because he works long hours and shifts etc.
So, AIBU to say to DB - well actually why don't you ask him?
Surely a text back saying "he'd probably be thrilled if you picked up the phone to ask him, his number is xxxxx" wouldn't offend DB? Personally I think if you're asking someone to do you the honour of being an usher (or bridesmaid, godparent or whatever) then its best, and comes across as most sincere, if its done either in person or by telephone at the least.
Is he likely to be asking because he wants your DH to be an usher and has just been too busy bone idle to ask before, or because the original usher has pulled out and they need someone, anyone to fill in to stop the bride having hysterics one week before the Big Day? (not that it makes much difference re your post lol, I'm just nosy like that )