My point was that it doesn't actually matter what's realistic, it matters what actually ends up in ARMA 3 / is chosen to be possible to be simulated (without modding) in RV4; I'm of the belief that ARMA 3 won't have melee by default nor will it have jamming.
But yes, as of right now it's still using the circle; I'm guessing that the build was intended to show off how much more fluid/smooth/responsive the shooting and moving with assault rifles/SMGs/pistols is supposed to be (I'd say transitioning if it didn't bring the character to a halt), not so much "oh hey we changed grenade throwing" hence why it supposedly didn't look different from ARMA 2.
While I am disappointed that weapon transitioning (and apparently a bunch of other actions) still bring the character to a halt, I remember Smookie's explanation for why on-the-move only "will be considered", and I am absolutely pleased with the pistol promise being kept! Thank you once again Smookie, you've set the standard against which all future ARMA pistol builds are to be measured! (Hint hint, anyone who was about to complain that the Gamescom ARMA 3 pistol was "too smooth and responsive"... )