I'm aware that some of the posters above are probably trolls, but I thought I'd respond so that people who don't realize that aren't fooled.
Vladimir was a 2:16 marathoner, I believe - maybe 2:14,I'll go back and double check - and he ran it when that time really meant something. If you're looking down your nose at what he does now, you're probably one third his age.
I used Van Aaken to lower my marathon/10k from 2:50/35 to 2:27/32. Slowing down and going longer works. If you don't believe it and aren't willing to test it out, don't. If you want to try something different that might make a big difference, if you have that courage, then I will tell you you will improve. Even if you don't though, the cost will be relatively little. It's hard to get injured at MP + 50% or whatever. You won't lose much in fitness, either, especially aerobic fitness. If you do the strides faithfully and a little speed work, you shouldn't lose much speed either.
I'm personally not so impressed with the 'new' training methods. Aside from all the supplementary stuff that runners do these days, the 'new' training is really old wine in new wine skin. Also, when I hear about super-secret stuff that the Moroccans or Spaniards or whomever is doing, I think, that the real innovation is that much of the training routes the runner through the pharmacy. No thanks.