I'm back from our WDW vacation and catching up... too much good information here to comment on it all, but I'm so appreciative of the questions, answers, thoughts, suggestions, accolades, etc.! Love these threads.
I did keep up my training at WDW and a thorough report is on my blog, but I mostly want to pass this along: putting in training runs on dead legs and an exhausted-by-Disney body isn't easy. I got it done and really did enjoy it, but wow - the heat, walking, standing, swimming, lugging around of luggage, inadequate sleep, etc. takes such a toll. I did my longest run yet there - 7.5 miles - plus two short runs and I'm still tired!
About the MM - I did one this weekend and I can see why Galloway recommends taking a few MM's, throwing out the slowest, and averaging the rest: I slept late, so got out later then planned, and it was brutally hot - there was a limit to how fast I could realistically push it, especially being so worn-out from WDW. I wound up with a 11:39, which certainly isn't bad, but it's slower than I know I can do under better conditions.
One min. jogging/running at that speed with the heat is about all I can do. If it gets hotter, I can only for about about 30-45 seconds. Ideally, for the ToT and maybe the Princess I would like to be able to jog for 2 mins, walk for 1. How do you work your way up to that?
I'm not Coach, but I've worked up to 1/2 mile run/ 1:00 walk intervals by keeping my walk portions at 1:00 and building up the run a little at a time. Say, from 1:00/1:00 for a few weeks to 1:15/1:00, to 1:30/1:00, etc. But only on short runs; long runs I do at whatever intervals feel best for my energy level and outside conditions. For my 7.5 mile I did 1:00run/:30walk and stuck to it until the last few miles when I skipped a few walk segments because I had some energy left.
As an aside, longer run intervals don't necessarily mean a faster run. I'm a pretty consistent 12:30-12:45/mile average pace, whether I'm doing :45run/:30walk or 1/2 mile run/ 1:00 walk; I run faster with shorter run intervals, slower with longer ones, so it all evens out. The big difference is in endurance - I can go longer more comfortably by easing back on the length of my run intervals, which is why I use shorter ones for long runs. YMMV, of course, but that's been my experience so far.