Just using yours as an example, there seems to be a few cuties on this thread that favour a 'dangling' straight legger. I like the pose, it looks cool as if they're saying, "Yeah, whatever" to the World.
So MANY photo ops lost! If I had my phone handy for every one of the priceless pics -- but no!I don't think his front legs can get any straighter, but I see what you mean. He's not doing the classic Superman pose. It actually looks like he's stuck in a hole or something, but no, he's got plenty of room. He was only like that for a second-I was trying to get a shot of him stretching, but was too late.