Someone with greater feint probably wouldn't wait to see if he is going to be attacked to make his own attacks. It seems to me a good maneuver when you are being outnumbered. The question including greater feint is because I paly thieves a lot. Still, anyone can bebefit from a feint if you manage to pull one. Attacking vs DV=10 is hard to miss, and even if you don't usually finesse, you could as well take the chance to do it to completely bypass armour.
The enemies you bluff are going to know that they have lost the sense motive check and after slaughtering one, or two(if your GM is generous) will attack other opponents instead. Or any that manage to beat your bluff test will attack you whilest the looses will aid them.
It seems possible to me that you could also know who wasn't feinted, unless he is trying to feint you as well, in which case he will have a single attack against you. In situations like these, the most probable case (unless your GM wants to kill you) would be that either you are being surrounded by a bunch of mooks, or a gang of mostly mooks with a more experienced leader. You can always choose which AoOs to deal. If you have spoted someone more dangerous among your assailants, then you wait till he attacks you, hoping that the mooks don't finish with you first. Mooks will have a harder time hitting you as well, since you have an imoproved DV, though they will begin to dilute it after the first attack, because of the stacked to hit bonus they get. This is interesting. You will only be able to defend more efficiently against a score of attackes, and the later will get to you when you are being overwhelmed so to speak. Still I think I like the idea. You could get a bonus of +4,+6 or +8 from total defense (total defense, tumble bonus and defensive martial arts).
As your character gains reputation and is recognised, more likely since your high level requirement to get Greater Feint, your opponents could very well have heard of your style and be wise to it before initiative is even rolled.
Indeed, and that's where you would want them, standing back. Of course they could see you, leave, then ambush you somewhere in a bad time for you.