RE: Power Jibe: how to flip the sail
The power gybe is the only one I ever learne to do, so I have had lots of good ones and lots of bad ones and I think I know the reasons for the difference.
The one key that makes the boom to boom work well and seem effortless and quick is this: When you are ready to flip the sail and have your front arm straight and pushing the mast/sail forward, and your back hand is sheeted in, you should make a quick forceful motion with both hands at virtually the same time. Yank the front hand(and therefore the mast) toward your chest while "throwing" the back of the boom away from you.
When you do this with the correct balance and with enough force, the sail rotates all by itself and the other side of the boom simply appears in the correct position for you to grab it amd hook in. This method requires a full commitment to the sail flip, but if you give it a solid push/pull at the correct time, it works like magic.
On the other hand, when I have done poor gybes, it has resulted from not such forceful front hand pull/back hand push, but I still end up never handling the mast, but rather grabbing the boom very far forward, near the mast after the sail flips. This is necessary because the sail has not rotated far enough to get both hands on the boom immediately.
The other thing that seems quite important is that the sail flip is done early in the gybe rather than waiting too long. If you wait too long, the sail starts to get somewhat backwinded, and the push with the back hand is not so easy to do.
My 2 cents worth.