Roger. Just to double check: Are we on the same page the old man's technique under scrutiny is
a)
do use managed descent
b) to shadow the FMC constraints with FCU setting, i.e. never relying on ALT CSTR(*) magenta.
exactly because
With busy airspace, and constant speed changes, the last thing I need as PM is to have to worry that the PF is gonna bust an altitude.