That's interesting. I've never had any problems with #2, and my abdominals aren't in in great shape-- I've never been able to do an unassisted sit-up. Even when I was a kid, I needed to put my feet under something.

The fourth Tibetan is the big challenge for me-- my chest and shoulders are very tight, and it took me a while to even realize that was the problem rather than the universe being out to get me. I've managed one rep of #4 that felt right-- like a coherent stretch across the front of my body.

One of the good things about T5T was realizing that I didn't have all the possible problems with the Tibetans. Another was one of the warm-ups (hands behind head, circle upper body) which improved my awareness enough that I could realize I was pulling against tightness in #4 rather than just having unspecified difficulty.

Some of the material about breathing in that book gave me some sense (no doubt incomplete) of how much I hold my breath.

I was going to start the second paragraph with '#4', and that paragraph appeared in large boldface. Markdown, stop helping so much!