Run/walk theory

Last night ended up going out pretty late for a run, about 9pm decided on a 45min easy run, and decided to trial the walk /run method, there has been some theories suggesting that this is the way forward for longer distance runs for example Ironman distance and marathons. I think I first heard about it on IM talk, a coach(I forget who) claimed even 3 hour marathoners can set new PB`s adopting a run/walk strategy, the idea is that by walking maybe 1 min every 8-10 min you can continue strong throughout the marathon whereas most people tail off in the last 10-15k this is especially true in an Ironman. Also by adopting it in training you recover quicker and are less injury prone, well that's the theory anyway. Of course you do have to practice it in training and the walk has to resemble a power walk..not a stroll in the park the idea is, is to keep ur cadence pretty much the same speed when you walk. Well it went ok and will persevere with the method a while longer ended up doing about 5.6 miles averaging 8min mile mainly in heart rate zone 2. I`m still yet to be convinced and starting to run again after a short walk felt a little weird, but I think I have to train my legs to adapt.