Thanks, Brendan - I was very proud of that! I had to check that Potter = Toddle worked, but Chambers seemed to confirm that it was fine (potter, to progress in an unhurried fashion and toddle, to saunter).
I was pretty sure of the answer as, surprisingly (at least to me), there are only a handful of words with that letter pattern and "toddle" was the only one that meant "potter", but for the life of me I could not figure out the parsing.
Thanks, Brendan. It was that meaning, use of Potter - walking slowly - that was new to me. Like you, I had the answer - but it took me a while to see how to get it. I think it was quite a clever clue - and not just because I solved it!