you don't want to 3bet steal with to many to act behind if you can help it..
You kinda do, if there are only 1 or2 behind you they will just 4 bet smash you
lol i know what you mean but i would 4bet any position,but in general the more to act the greater the chance , all about opinion and image and every situation is different,so i guess there is no set rule to 3betting..
if he is playing a 15 to 25bb stack though flushy a 4bet steal is un-likely with tripe..unless it is a complete sicko who has read the situation perfect has a big stack ish

[not always the case] and is willing to race with the 15to25bb stack who is pot committed after his 3bet..