Schweik:"I dont use my thumb straps as a pivot point,on my english,I have them very loose so that i can move my hand easily."

RE:That means that to alter between the low and high parts of the keyboard to reach all the buttons you slide with your thumb in the thumbstrap and with your little finger along the finger rest - isn't that so? In that case you meet the situation that either the stability is generally poorer (than with a more fixed thumb position and rotating the hand with the thumbstrap as "pivot") - or you have to grip steadily with your hand to create necessary stability resulting in static effort that we wish to avoid as far as possible