I never contributed to this thread, but have been watching from the sidelines for a long time, and I think sharing my exeperiences at Boston today might give other people who ran some much-needed perspective.
I was trying to break 2:40--I've run the race 5 times now, and the best I've been able to manage is 2:45:52. I have always struggled in this race, too. I've often toed the line fit enough to break 2:40, but the mistake that I have repeated (now) the past three times I have run this race is to go out too fast, end up blowing up, and invariably crawling toward the finish.
Let me start by telling you that I saw the warnings in the e-mails sent out by the BAA. Despite hearing other runners talk about how they have slowed 10 seconds or more off their goal pace during hot years, I treated those warnings like they were for someone else. "I'm fit, so the heat should affect me less," was my line of reasoning. I also stupidly believed I could "out-run" the heat (get off to a fast start, and bank time before the heat effects you--in short: a TERRIBLE idea.)
I felt great in my first four miles, which were a 5:45/5:45/and a couple of 5:5x's. I developed a slight stich in my right side, and had to slow down a bit to recover--hey: my next two miles were under 6 mins. I believed that my strategy just might work. I envisioned myself crawling up heartbreak hill only needing to run the last six miles in near 7 min pace. And I plowed ahead. A couple miles later, I had a stitch on the other sode of my stomach. Now I couldn't breathe. Also, I realized that I was getting fatigued: I felt like I had covered about a half marathon, bit still had about 18 miles to go.
So, without asking myself a question that I will reflect on later--"why does this keep happening to me?"--I pulled over to the side of the road and walked. The crowds at Boston are wonderful, very supportive...but I hated them. I hated it every time someone asked if I was OK. I hated ot when people shouted encouragement at me, trying to pick me up because I was obviously having a bad day. I love the people, but hated the crowd. And while I was busy hating them for their kindness, I noticed something: my head was absolutely throbbing from the sun beating down on me. So when you have physical symptoms that you aren't prepared to deal with, and youv'e got things going on in your mind that distract you from running, you are off to a pretty bad start.
Let me shorten this quite a bit by pointing out that, once I started running again, I was still ahead of the 6:06 pace I was hoping to average. I had visions of running an even split, or--better yet--pull off a highly-unlikely negative split. I'm not saying people don't negative split at Boston--just that those who do are those who do a much better job of planning than I did. Make it through the hills in Newton with anything left and the last five miles practically beg you to run fast, but that has more to do with your ability to regulate your effort than an iron will. One thing i can say for sure is that this Boston held the most bizarre experience I have ever had while running the race: as I'm flying through the "scream corridor" at Wellesley, my stitch returns, I can barely breathe, and I look down and say "Christ...how long does this thing go on for?!!!" because I don't want to start walking until I'm out of earshot of all of the enthusiasm on display. Needless to say, after walking portions of miles 13, 14, and a prudent decision not to run the length of Heartbreak, I was done. It was now a struggle to keep under 7mins/mile, and a few of my splits balooned into the 8:30 range.
I am writing this at the airport, and it's good to see so many smiling faces on runners, all of whom, without exception, have had terrible days. If you ran smart and finished strong, then congratulations! If you made the same mistakes I did, then don't feel bad. I don't think I would habe forgiven myself for not trying to run the time I was chasing, even though it was pretty foolish to do so. (As a side note: this is the second spring marathon in a row that I have had sabotaged by unseasonably warm weather.) I wish things had gone differently, but they didn't! Ended up mpre than 15 minutes slower than the time I wanted to run. It hurts, but the pain will go away, and hopefully I'll be smarter next time (prob not: hopefully the weather is kinder, though!) If you ran, then you just experienced what it was like to run in one of the tougher years...you should be proud of that!