littlebabyjesus
one of Maxwell's demons
I agree that it's not a bad tactic from her. Only tactic available to her. But she has to get this through parliament. The day there is a vote against this deal (or as you say something very like) is the day May resigns. I think we can know that much. But no date has been set for that vote, and if there is a vonc in May and a leadership contest, would, could or should that delay the commons vote? I don't know - you could argue that such internal party affairs shouldn't affect important time-sensitive commons business, or you could argue that this commons business needs a pm who is not in the process of being dethroned.She thinks that as the deadline approaches many of the spineless pricks that inhabit the HoC will back this deal (or something very like) because the whips will twist arms, and a number of MPs will either don't want no deal or don't want a continuation of A50. As a tactic it's not unreasonable (from her perspective).
There isn't actually a deadline for any commons vote, as I understand it, which is a bit odd. Delaying it as long as possible would seem May's best (only) strategy, and then as you say relying on spinelessness. Whatever happens, she'll need a fair few labour defectors, so she'll also need some discontent to be forming there. I'm not sure there has been much more to her strategy since the last election than 'just cling on'.
If this deal is voted down by the commons, I think a second referendum becomes a very likely thing. For all the posturing, nobody wants to be in charge on the date of a 'no deal' deadline.