We tried doing that today - but not too hard as Tyler is developing a bit of a cold so I don't want to push him... I'll just deal with any extra night wakefulness if needed until he's feeling better.
What do I do though if I try to lengthen out the A time and end up making one or both of them OT? Dylan seems to have a very narrow sleep window - if I catch him at the first yawn for our wind-down, he goes down really well, but if I take too long, we have a huge struggle with Dylan crying off and on for over an hour. Shh-patting doesn't seem to work well with him (he just gets more wound up) so I end up picking him up until he relaxes again (although I might be creating a prop that will become hard to break if I keep doing that!). Tyler seems to handle it better if we miss his sleep window (in fact he will start drifting off while laying on the playmat or blanket on the floor ;P)...