Hi Bill
Do drill bits for use in ordinary "home use" drills get blunt with
the result that they work less well?

Yes they do, how fast depends on what you are drilling. My 50's built house
has cement render on the internal walls. Masonry nails bend if you try to
hammer them in. I destroyed 4 x 6mm drill bits putting in new skirting &
dado rails in a 30' x 15' room.

Dave