Last week I ran a full effort marathon. Weather was terrible (18+mph) wind, and I brought home a 2:47.
I don't think I could have done more in those conditions, but I believe with less wind I could have gone very close to 2:40.
However, I'm recovering fairly well and I carried on doing 35/40 minutes jog every day this week.
Next weekend I have a place for another marathon, and the weather looks fine. I'm very tempted to get there and run a just-sub-3 for fun.
What's your experience/advice on back to back marathons? Is a 2:58 target too ambitious after 7 days?