I don't remember if it was "Deadly Assassin" or "Invasion of Time" but there was one bit where two Time Lords were chatting with each other and they very casually talked about oh I see you've regenerated yes I thought it was time for a change do you like it?
If every regeneration is one step closer to death, isn't it a little odd that they treat it so casually like getting a face lift?
I don't remember the dialogue, but there is the Doctor talking to a reporter in Deadly Assassin with something like that...
A lot of timelords seem a little self involved, plus I doubt they'd care much about the rebel type getting closer to death.
I remember being quite young when I first saw it and that being the first time I saw a timelord recognising another despite regenerating. I remember explaining it to my sister as like a cat still recognising your scent when you've grown a beard and cut your hair. Which was odd...