Dannirr There are those with a LOT more experience than me but if it helps I set my marathon PB as part of my training for Comrades in 2013. Didn't even think about it until half way felt good so went for it. May have been a different story if stood on the start thinking about it.
Good speed work going on. I managed 50;40 at a 10k last Friday it was hot but I gave it everything for sub 50 but not to be. been doing spin class last couple of weeks at gym to give the legs a break and to my surprise enjoying it. Maybe just maybe a tri would give me a fresh challenge
FRC report is fantastic really gave the feeling of being there