There is a pub called the Watling just by Mansion House tube.
It was a perfect base for watching the women's marathon. It is less than a min walk from seeing runners head down Cheapside and then return past Mansion House 15 mins later; time for a quick pint and then repeat * 4 and then head back to pub to watch the finish
I would do long runs at 8:15 ish and do the last 3 miles at 7:30 ish. This would bring my average pace a few secs above my target marathon pace of 8 min miles.
For long runs over 20 miles would feel v exhausted at end - 8/10.
When I ran London last month was able to grind out pretty even 8 min miles with a lot of concentration and some pain for last hour but felt no more exhausted than after long runs. Also, this was tempered by hitting my target of sub 3:30 with 30s to spare
I spoke briefly to him right at start where he was an oasis of calm. He said to remember that if you have a bad mile, you can recover and then advised that he would do 1st half in 1:44 and second in 1:46. I said that I would be heading off a tad quicker and he may pick me up at 21 miles.
Sure enough that is exactly what happened and his presence really was very much appreciated; a few words of encouragement here and there were ideal and then suddenly we were going down the hill to Blackfriars Bridge and I overheard him telling another couple of runners that if they were still feeling 'ok' at this point, they would make 3:30. It was only at this point that I thought that I could do 3:30.
Again, a few words of encouragement along Embankment and I was able to grind it out for the last wee stretch with the threat of cramp ever present! Made it with 30s to spare