OK. Went back to the range. Rented the trusty 'ole 226, and added a training cap to my box of live ammo.
Boss said "DA only, tonight. One shot at a time".
Warmed up with the dummy cap, just to get a feeling of the DA only pull.
Pretty hard on my index finger.
Popped some rounds @ 10mt (33 ft). All were falling squarely in the pie-wedge between dead center, 12 o'clock and 9'o clock. The curse of the "left".
Tried modifying my grip, tried different breathing rythms.
After 50 rounds, 80% fell in the pie, the rest being in the paper, on the left side (again). Found that I didn't really need to strain in order to aim properly, even though my sights weren't really very sharp (a combination of so-so lighting and plain old sights w/ no contrast whatsoever) - not bad IMHO.
However - I played some more with the dummy cap. Really watched what was happening to the barrel itself. Basically, since my index and my palm are pretty long when I grasp the gun, the base of my index is practically aligned with where the trigger will need to be in order to release.
I.e. I'm folding my index so much that I need to "push" with a slight rotation of my hand in order to compensate for the very uncomfortable position.
My index joint is acking like cr*p today, trust me :-/
So that's the long and short of it - I need a wider (longer?) grip, and/or a shorter trigger pull (apparently impossible to do on a regular 226).
Tomorrow I'm going to shoot a swiss Sphinx pistol that someone is kindly lending me. I've held it for a couple of minutes, and the ergonomics and the trigger distance seem to work better.
Will let you know what happens