You could get a faster marathon with either approach to be honest. The thing is, once you've got those 'quality' sessions in, there comes a point where extra running has to be at easier pace - nobody would suggest 100 miles a week flat out, or lots of long runs every week, is a good idea. It's not correct to say that those extra run sessions are a waste of time, but equally swapping them for cycling or swimming won't make too much difference to your running.
One point though is how are you looking to get this faster time - did you slow down significantly in your marathon, so you want to start at the same pace but stay on it for longer (in which case you need to build more endurance and those extra runs might be better) or was your endurance OK but you need a faster basic speed (in which case a bit of focus on speeding up the shorter stuff might be the way to go)?
Even better, you could volunteer to do the tokens yourself and see if you can spot how it could be done better?
At my local one, the person handing out the tokens calls out the finish position as he hands it over, so the finisher knows what position they're in before they look at the token (the volunteer is obviously checking as well but at times the finishers are coming in too quickly to check each one individually).
Of course, not everyone looks at their token before they hand it over, but enough do that if they were being handed out in the wrong order it would get picked up pretty quickly. As far as I know, aside from the odd missing token they've never had a problem in over 300 events.
Nice HIM blisters. I've had a few tris like that, where you think you're a bike god because nobody passes you. Then I do a duathlon and find out I'm very average...
Mixed weekend for me: quickest parkrun for a year & a decent bike saturday, yesterday an early swim and 13 miles largely off road in the afternoon which started OK but finished doubled up with stomach cramps. Too big a lunch, probably.
Saw The Who saturday night too, and junior did a triathlon ata his school sunday morning, so on balance a good few days.
At the end of the day it's all about getting to the finish as quickly as possible, and if that means a run-walk strategy, or walking the aid stations, then so be it. Personally I wouldn't start training for an IM with a run-walk as a plan, but I can understand why others do.
I wouldn't regard walking parts of the run as failure either, any more than I would think that freewheeling down a hill on the bike leg was 'failure'. It's about efficiency over the whole course. I've walked aid stations on every IM I've done, and I can pretty much guarantee that it's been quicker than if I'd tried to keep running through.