From: Phil Edwards - PM
Date: 26 Apr 12 - 11:03 AM
"Another one for the EC players - how do you prefer your thumb straps? Mine are very loose (and don't appear to be adjustable, unfortunately);"

With all concertinas you've got the conflict between a)need for stability to manage pumping and tonal control b) flexibility to manage fingering and to reach distant buttons. The major problems here with the EC are: 1)the thumb strap offers too little stability 2)the little finger is too weak to add support 3) gripping with the thumb AND the little finger results in static crampful load which obstructs movements, particularly of 3rd finger 4) gripping ( as C Wheatstone intended) 3rd and 4th finger may offer stability enough but veery poor access to the keyboard 5) using the trad wriststrap locks the hand in a dysfunctional position.
Some dilemma...

I use a broader (30-35mm) thumbstrap so that he distant joint is locked, it is also steadier and stuffed to be thicker so it becomes more comfortable when set tight with the thumb far into it. This increases stability so that all 4 fingers may be free. With a treble this mostly works ok (depending on the music demands). With larger instruments I always use an additional wrist suppport and wrist strap to achieve more stability while the hand can slide and rotate with the fixated thumb as a pivot. To reduce load on the thumb and wrist I also hang the instrument up in a shoulder strap.The important objects are relieving the thumb and the fingers from any duty related to carrying the weight of the instrument. Fingers of course should be entirely free for "fingering" of the buttons.