Thanks Antonio - what perplexes me is how important preparation (especially the mental type) appears to be. I can already run two hours non-stop with relatively little problem having run a 2h13m half marathon without a walk break just four weeks ago. But then out of the blue I've had a couple of tough runs such as yesterday that have been difficult to complete. I really think it's a case of the "body is willing but the spirit is weak" because in reality many of these runs aren't that difficult. The only difference seems to be preparation (or lack of). Yesterday I was mentally under the gun because I only had one small window of opportunity to get the run done and that was early in the morning and I simply wasn't mentally ready for it.
I have been an advocate of the run/walk strategy in the past and it certainly is useful for getting started and in overcoming injuries. I think the basic problem with it though is that if you need to recuperate every few minutes then obviously you are running too fast. If instead you find a steady, slow pace that suits your level, then you can settle into a rhythm that I, at least, always struggled to find when adopting the run/walk method. And judging by the numbers of run/walkers I played leapfrog with in my last two races, I'd suggest I wasn't alone in that. Most of the run/walkers I saw were simply running way too fast. We need to get them on this forum so you can coach them Antonio.
Doubtless when we get our RC club colours that will begin to happen!