Okay, My best half marathon time this year is 2.09.34 way back in February. Recent half marathon times 2.33 and 2.42 (not much training and coming back after injury).
I started running in 1999 and ran for about a year, took a break for 6 months and then started again so running continously for 3 years.
My splits for Loch Ness, halfway 2.39 and finished in 5.28.
For Lochaber halfway 2.25 and finished in 5.40. Wasn't use to running in the afternoon, and didn't feel right on the day.
For Abingdon 2003, 2.27 half way (I think) and finished in 5.11. My best marathon time.
I find it hard to concentrate on the correct pace throughout a marathon, it is a long way. I think if I start to fall behind too much I lose the drive to work hard at the pace and maybe give up? I find the hardest part of the marathon around 15/16 miles and once I pass 22/23 miles I tend to pick up again. It is the middle parts of most of my races that I do find the hardest. Haven't done emough marathons to know why?
I actually find training for the marathon the hardest part, if you don't get this right the marathon itself isn't going to go correctly.