That would be my thought as well; after determining if the line was hot or not. :-) Those look bigger than what I would want to tackle with limited experience and a little homelite. That mid-suspension, wires under tension, that adds some new dynamics to a felling and bucking problem.
What I wondered is if there's elasticity to the lines, so as you remove weight, would it move? Doesn't look like it from that last one I just posted, but others, maybe it might.
Yes, good point about the wires under tension...I'd rather let a tree expert go after it myself. Even those guys get hurt sometimes, I believe.