Great advice. I want to emphasize #1 for anyone who's considering following the marathon training plan in the NY Times article.
The suggested marathon training plan has you doing a 9-mile run on week 4... And then 23 miles and 26 miles just a few months after starting to run (presumably). For a beginner, that's just begging for an injury from pushing too hard. Even for seasoned runners, it's not necessary to reach 26 miles when training for a marathon. Getting to 23 is usually enough.
I've done a marathon with no training once...it was a very miserable experience, and unsurprisingly my worst time ever.
In general, training is good, the more you can get in, the better, especially for beginners. Unless you're starting out with extremely good overall fitness, it will take a while to get to the point where you can finish a marathon without too much pain ir risk of injury.
The marathon demands its pound of flesh. I prefer to pay for it during training. (Of course, that's no guarantee I won't pay for it again during the race, but if that happens, it's probably because I was racing too fast.)
The suggested marathon training plan has you doing a 9-mile run on week 4... And then 23 miles and 26 miles just a few months after starting to run (presumably). For a beginner, that's just begging for an injury from pushing too hard. Even for seasoned runners, it's not necessary to reach 26 miles when training for a marathon. Getting to 23 is usually enough.