I agreed about the imprecision of extrapolating - it may show "OK, this is possible" but it certainly doesn't guarantee anything. As far as 5K fitness, I'm nowhere close to PR shape, but the 200 shows me it's not because I can't move my legs fast anymore.
-Track is easy - 1/2 mile from home. Planning on 6-8 x 800@5k pace tonight.
-Runs from home are roads, but I have and use trails nearby frequently.
-PA actually (outside Philly) so I have every type of hill you could imagine.
-Historically it's been the latter, but I do recognize I should be more disciplined in the effort I put into track workouts.
You were right about it being hard to argue with Magill's results and the simplicity of his program fits with my general way of doing things. For the sake of getting started with some focus I penciled 4 base weeks and 2 race weeks into my training calendar.