I didn't mean to compare Walmsley and Droddy as athletes, just point out that the marathon equivalent of your half-marathon PR isn't a given. Especially not the first time you run a full.[/quote]
Look, I'm neither a fanboy nor a naysayer troll. Just a dispassionate observer. It's a bit disingenuous to say "...especially not the first time you run a full (marathon)" to infer that his half marathon time shouldn't be expected to translate to a good first-time marathon.
Dude has a proven record at 50k, 50 miles, 100 miles, etc, and literally runs 26+ miles a couple times a week. I'm not saying he's likely to make the Olympic team, but come on, he's not likely to blow up like a true first-time marathoner either.
I happen to think he'll finish between 6th and 10th in Atlanta. So I'm a bit on the high side of the continuum that runs from "he's the 243rd qualifier" to "top 3 for sure." It sounds like the course was a little short this morning, so assuming a 1:03:15 actual HM, I'd project that out to 2:13:30, making him perhaps around the 10th best American, but I see him placing a bit higher in Atlanta as the hills might make some faster runners struggle at the end.