That's what Fergie does, yes. But I think it would be more beneficial to just stick with De Gea as number one whenever he's fit apart from the odd game to keep Anders warm.
Well, I cant argue about subjective opinions so that's fair enough. I think Fergie realises the potential of both goalkeepers though, and dont want to lose either one of them. I think right now that they are at a similar level of ability, which is why it would be unfair (in my opinion) to make one a clear first choice without anyone of them deserving to be dropped.