The link below convinced me that the iambic or squeeze keying is not as beneficial as we like to believe it to be.
Iambic Keying - Debunking the Myth
by Marshall G. Emm, N1FN
The letters that can be ‘squeezed’ are: C, F, K, L, Y, Q, R
The most common letter used in the English language: E,T,A,O,I,N,S,H,R,D,L,U
So the only squeezable character in that list is the above list is the letter “L”
I think we were conned, the theoretical benefit of iambic keying is negligible.
Then there is the mechanical aspects not discussed anywhere as far as I know. With a dual paddle two independent levers must be moved in the same direction (most of the time) and they must act as if it was one solid lever and at other times they must act independently from each other. If one considers the tiny gap between the contacts and the miniscule rotational movement the light return forces (springs or magnets) the light contact forces then one might appreciate that a single lever must be better suited at this task. IMHO the chances of a mechanical hick cup due: to friction, non-return to neutral, poor contact resistance or tracking errors (non-existent) and inertia etc. must be halved when using a single lever paddle.
Let us be honest. Most or many of these errors may only be evident or be unacceptably bothersome at very high speeds. I am not a high speed operator, but a key that works for a QRQ speed freak will simply be perfect when used at normal operating speeds. I would like to be competent (comfortable) at 35 WPM for working in contests and with DX style exchanges.
The only problem with the transition to a single lever paddle I foresee is that I will no longer have a reason or an excuse for my sloppy sending errors.
I am now looking forward to receiving my Begali HST single lever paddle so that I can try and confirm or dispel my theories.