I assume you are referring to the Hit Me article.

I have completely unintentionally validated this approach for endurance training/racing. Thinking my triathlon and endurance days were numbered, I switched to working out in timeframes that fit in my continually adjusting lifestyle. Kids, (3 diff jobs - ok two are coaching related), and house remodeling have consumed vast amounts of what used to be ample training time.

When approached to do a ride with people that had been training all summer, putting in long miles and big climbs, I accepted knowing full well I hadn't 'trained' enough. All I was doing was short bike commutes to my day job (14 miles each way) and HIT workouts 3 days a week (I lead them). I accepted this ride assuming I would be dead at the end of the ride, and completely useless for days.

The exact opposite happened. I flatted early in the 70 mile, 6000 ft elevation gain ride. The group left and I was faced with the option of trying to catch them or just enjoy the ride. I even contemplated turning around. I stuck with it.

I caught up with the main group.

Then, I passed them. I went to the gift shop (at Mount Hamilton) bought a couple shirts and waited for the group to arrive. They didn't. They turned around early.

I caught them again.

This is 50 miles into the ride. I should be toast.

I continued to ride with them and finish strong.

I attribute this ride to HIT training. I was shocked.

It's worth checking into. Not a replacement but a training option. Think about it.

1. Yes, the article focused mainly on cycling. The "rest" when you are doing an interval workout in cycling is really, really easy spinning. Say you do a three minute interval near VO2 Max, spend around the same amount of time doing very easy spinning. By the time the next interval comes around, you should not really feel too much lactic acid built up anymore in your legs, until you start the interval.

2. You can definitely train this similar way with running. However, the rest in running can vary. If you do a longer tempo/longer interval workout, then normally your rest should physically be to stop and rest for 2-4 minutes (as you called it a complete rest). For example, if you are doing 3 X 3200m or anything beyond that distance, you should NOT do an active rest (which is jogging very lightly as your only rest). For that kind of workout take around 2 or 3 minutes in between each interval, depending on how you feel. However, if you are doing a quicker workout, say 8 X 400m or 4 X 800m, your rest should be active (jogging 400m as a rest, then go right into the next interval). This teaches the legs to be able to put up with lactic acid buildup. When you have an actual rest of 2-4 minutes of not doing anything, the lactic acid in your legs almost goes away until you build it back up during the next interval. You should incorporate both kinds of workouts into your training regimen (as long as you are not training for an IM, because in that case speed is not such a monumental factor as is finishing)