I have since learned from a friend that Crosscut saws (where the teeth go in line) are much better than Ripsaws (where the teeth go at opposed angles) I think this is the same point that Bev and Jerry is (are?)making.

About 2.5 to 3 foot is the optimum length and if you have weak knees then bolt the handle to a plank and sit on the plank astride the saw.....

I'm just off to the shed to try mine out...