Oh yes they do! Certainly we've had a few runway incursions over the last couple of years after the ATCO has said "taxi holding point G6 and report ready for departure" and the pilot has taken that as line-up clearance. I've also had it the other way, where someone has been at the holding point and I've cleared them for take-off, then they've replied "Runway 21 cleared for take off, confirm I can line up?". Yes, that generally sounds like a good idea.