It doesn't work. It just doesn't work.
This feat is a running joke.
It is the only feat, as far as I'm aware, that has absolutely no benefit whatsoever. You can't even use it to pick up objects at a distance, as the reach only applies to attacks (which you cannot make since you already used your standard action.)
Nicos, are you talking about Prone Shooter? It seems to have been errataed to have two benefits: your AC against melee takes a -2 instead of a -4, and your AC vs ranged attacks gets a +6 instead of a +4.
Monkey Lunge, on they other hand, they seem to have no interest in fixing. They even marked the FAQ request as "no reply required".
RAI: You get one attack as a standard action which doesn't take the -2AC penalty and gains an extra 5' reach.
RAW: You spend your standard action to look like a monkey. Congrats.
Clearly they made it anticipating the mythic rules granting extra standard actions. Right? ... Guys..?
OH! I've got it!
If you have a wordcasting friend with Borrow Future, and he readys to cast the spell when you monkey lunge, then you get to add reach without -2AC penalty, he casts spell, allowing you to immediately take a full-round action, and you get a full-attack with 5' extra reach!
The target of a wordspell with this effect word takes either a standard action and a move action or a full-round action immediately after a wordspell with this effect word is cast (maximum once per round). The target skips its next turn, but any effects that would occur on its turn or spell effects that would expire on its turn occur normally. The target is not helpless on its next turn, but can take no actions.
Come on guys you know that they are waiting to put out a sequel book with another feat that fixes it. I mean why check rules before hand or issue simple errata quickly.
Improved monkey lunge: you must now use a full round action to perform monkey lunge. In addition +5 to disguise checks while performing a monkey lunge to impersonate a monkey.
Could you use Monkey Lunge with a readied action?
You mean, could you ready to use it? Yes, but it still wouldn't do anything.
Also, are you allowed to Overrun multiple creatures? I always thought you could, although I can't find it in the rules. If you could, though, Elephant Stomp wouldn't be completely useless.
If you could overrun multiple targets, you could do something like this with Elephant Stomp:
T = target
M = mook
Y = you
# = wall
_ = empty space
#T#
#_#
#M#
#_#
#Y#
You could overrun the mook, overrun the target, and if you beat his CMD by 5, make an attack against him.
You already used your standard action to overrun. But yeah, Greater Overrun is just better - UNLESS the target can't be knocked prone.