I can't believe I'm reading your last post - maybe it's time you reconsidered your career. You're not really going to tell me that an ATPL/CPL needs to be warned that low collective settings can result in excessive rates of descent when the AFCS is coupled to VS are you?? If so you just should not be flying - your understanding of basic physics, let alone absorption of training, is simply inadequate.
Sorry rotorspeed I didn't say that. I said an ATPL/CPL needs to be warned that a basic 3-axis AP in ALT/VS with depart controlled flight due to loss of AIRSPEED if the collective is lowered (and held too long). Not as intuitive. Let me guess - you have never tried it - it is extremely subtle until it suddenly goes. And no, I haven't just mucked about while flying, it was done under controlled conditions to see what happened. Let's be honest flying with collective for speed is not intuitive.
I do think dumb 3-axis autopilots (not latest EC in EC135 for example) are more dangerous than they are worth - I'll say it again, an AP shouldn't be able to take the aircraft into a dangerous flight condition, certainly not on Public Transport. GM