However, what is taking longer for Duke is the house training. OK, it wasn't his fault that the pet shop was out of the food I'd started him on, so had to switch to a different food which contains salmon and oats - no idea if it's the salmon or the oats that disagreed, but a very runny bum and consequent overnight piles on the landing was the result (thank goodness for Vax, who make a really good carpet washer...)
The danger time for piddle seems to be straight after breakfast: he has a definite routine: Get up, pee (outside), eat breakfast, then pee again straight away, much more generously - as close as he can get to his breakfast dish! It would be easier for me to prevent this if I were more of a morning person, but I have to get more thorough with the supervision for a while I think. I was assuming that now he's being generally so good with the cats I could let him offlead around the house, but clearly he can't handle that level of freedom yet, and will need to stay onlead a bit longer.