Specials Attack Strategy - How'z it work?

Perhaps I am wrong to assume that there is some logic in this, but why does my Fling Shot sometimes hit for 1 and other times for 100? I understand Critical Hits and am not talking about that.
What I am wondering is whether anyone has worked out any method to making special attacks hit harder?

First, is time available a factor? Do I need to wait longer than just letting the special attack regen in order to get it to hit harder?

Then, wondering about the yellow attack bar that inches to and fro during my combat. Is that all for looks or do some special attacks work better when the yellow bar is at the far right and others when it is at the far left? Note - try using Fast Attack when the Attack bar has maxxed and is just starting to regen, it would seem that it hits harder there - but that may just be wishful thinking...

Someone correct me if I'm wrong, but:

Fling Shot is just an extra attack, like any other. The value is that it's instant and additional, but it does the same damage as any normal shot from your weapon. Therefore if you're a soldier with a 1-100 energy gun, that's the range you'll do (plus modifiers, blah blah blah, of course).

Also, the attack bar simply shows you your attack speed. It's a function of the weapon (a 1.35 attack is almost twice as fast as a 2.50 attack, etc.) and the attack type (it takes several seconds to empty a clip with Full Auto).

Anyone else?