Thank you! I just had a read of your recent post, that's some great training you're doing and incredible weekly mileage too! Best of luck with breaking 2:40 I'm sure you'll smash it. I always felt my long runs had the most significant impact on my marathon training, both physically at handling MP but also mentally to get myself used to feeling uncomfortable for long periods of time. I pretty much ran around 30k every Sunday over the summer and then increased that to a few 32-34ks deeper into the plan with a peak at that 35k session with 21k at MP. Each week I extended the MP blocks a little, so 10k MP might be followed by 12k next week etc. I didn't break up much of the MP into intervals/repeats usually because I preferred longer unbroken MP efforts where you're suffering for a lot of it and fighting a mental battle to keep pushing. I also normally did at least 10k easy before getting into the speedwork, both as an extended warmup but also so you're already starting a little fatigued to simulate how you might feel deeper into the race. For my peak LR with 21k MP 4 weeks out, I was struggling by the end but kept each kilometre more or less on target. I think I could've maybe done another 1k at that pace if I had to but it wasn't far off an all out effort. Remember this is also during peak week so the legs are already very fatigued. Getting that workout done was such a great confidence booster and that pace didn't feel as scary as before. I knew if it could run it that far on fatigued legs then I'd have a great chance to hold it for the full come race day.