So, I won't spoil Smurf's report, I'll just say I did what I said I would. Ran the half, was thinking of 5min pace as that's faster than the training I've been doing but ended up with about 4.52. Can't complain tbh. I was feeling ok and then with about 2k to the half I wasn't. So the hope of doing another bit to get me near the start/finish was ditched and I stepped off the course about 1 metre after the Halfway mat. Legs immediately felt awful, like I'd done a full. Knees and left hip were weirdly ok but there were other issues. Anyway, it is what it is as Plato said to Sophocles. Don't think I'll return to 42.2 anytime soon, tbh. Glad I didn't sell the bib though, I was part of the event and everything that comes with a big city marathon.