Is taking off your dog's collar when he's inside a good idea?

• Our senior Lad always wears a collar with our phone number because he's getting a bit senile and sometimes wanders off.
• New dogs or visiting dogs always wear collars with our phone numbers in case they get away from us and can't find their way back
• As do our dogs when we travel, for the same reason.

Again, don't worry about what you did with your previous dog; it really didn't matter to him. If anything, it was nice of you to let him be free and natural in his last days. As for any future dogs, do the same for them when you can, while making sure they wear collars with contacts in any situation where they might get away from you (and when in doubt, erring on the side of over-wearing is obviously better than them being found somewhere they shouldn't be without).