This all seems to be a recipe for ensuring that nobody volunteers for the army or TA ever again.

AFAIK, no member of the Territorial Army who really didn't want to go was made to - in fact, because of the rather clever way the system works, most people that went were probably volunteers but no official stats are kept - SNCOs will know everyones personal preferences and can pass that up the chain. Everyone is treated as a compulsory call up as it causes less trouble with partners/employers etc and if you really don't want to go you can just deliberately flunk the fitness tests.