Heavier objects have more momentum and take longer to decelerate. They're not saying heavy fighters climb better because they are heavier, they are saying heavy fighters can bounce back up and regain a lot of E quickly if they don't blow their momentum. The AHWiki stresses this fact several times when talking about aircraft such as F4U's, F6F's, and P-47's. Search for the word "zoom" in any of the aircrafts' bios: http://bbs.hitechcreations.com/wiki/index.php/P-47D-11
If the rest of their claims are about as unrealistic as that example I think someone needs to do less dismissing and more listening.
<- at myself.
Yeah, I kind of stepped in it there. Let me explain.
I understand inertia and drag just fine, the whole F=MA equation, therefore a heavy fighter can carry more force into a climb. My example was unclear. What the people arguing didn't understand was gravity. The argument I was referring to was that a Jug could dive faster because of gravity, that gravity "pulled" it down faster giving it more speed for a zoom climb. Yes, a Jug can dive faster, but it is because more drag force is required to slow it's inertial force, not because gravity "pulls" it more.
Another one of my pet peeves is how many people misunderstand how jet propulsion works. I was talking with a moon landing hoax guy the other day, who said it was a hoax, because rockets can't work in space because there is no atmosphere for them to "push" against. I tried to explain Newton's third law to him, and that that's how jet propulsion works, but he never got it.