Hello

After reading a few post and recommendations on how to obtain more miles or points faster. I have this question, which I could not find; I might not have search well enough.
Anyway, is it possible to open separate accounts for spouses for same type of credit card and get bonus mile on each account, and then combine these miles when obtaining tickets?

Or in another case, some cash back cards have annual cash dividend limit. Is possible to open separate accounts for spouses and double cash dividend since everybody would be using their own card?

thanks