If a monster doesn't have a full HP scale, it will regenerate whether you attack it or not. Moreover, the first portion of regeneration can occur immediately after your first shot. Or it may come a little later. And if you kill him before that moment, he will not regenerate at all. It seems that...
These are such ancient quotes that I even feel sorry for those people who think that nothing changes with time.
There's also a quote from the same Marco:
Do you really think that under Loot 2.0, MA income continues to include weapon deterioration?
So, all of the Marco quotes you cited are from...
Open the auction window and see that weapon amps are one family, mining amps are another.
And you talk about weapon amps, then jump to mining amps, and yet you call it all one family.
For the purposes of your discussion, it is very important to separate them.