In the Programm select mode (when the red ring is around the LHS Select knob), A and B switch are respectively dec and inc programs. can they be on demand as Dec+Load and Inc+Load as proposed if using ext switches?
No, these only function in a search capacity. Have you experimented with BANK mode? Hold down the SELECT knob for a few seconds. In this mode, you will be able to recall a program instantly by pressing a footswitch. You get three per bank.
I understand the point. However, this unit will be used by the singer of my band as its controllable vocal FX. I’m trying to find the simpliest way to operate with a minimum of switch press. I think the best will probably be to use such ext device : https://www.pigtronix.com/pedals/universal-remote/
in order to have direct and permanent access to 2 switch being Inc+load and Dec+Load while the third one will be Preset A Bypass (A will always be specific needed FX in the song like temp Harmo or delay while B is a permanent Reverb)
Sorry, to finish, using that ext switch will avoid the singer to have more than 1 switch press (going in Bank mode is 1 press and hold plus selection, going in perf mode is 1 press and hold plus switch layering).