"- and insists that there will be no drilling into the Amalgam itself but all around it. My feeling is that this may cause the collapse of quite a few of my teeth as they are heavily patched already. I am determined not to let him do root canals if this happens."
And you are the experiment.
IMO to remove Amalgam fillings you drill them out from the center and into pieces. You dont touch the fresh tooth material until the Amalgam is removed. And only minimally then to remove some of the amalgam staining.
If he actually does what you said, he will be removing a lot of tooth material which may be painful and cause the death of the tooth. If that is his plan find another dentist. Of course such a plan will reduce his exposure to amalgam vapors.