Thank you all for the feedback.
Terry - I understand what you are saying, but I guess what I am getting at is finding good balance between practicing and training. You said it yourself in the book:
"Alas, that’s not what I meant. We’re adjusting priorities, not advocating sloth. In the first place, 30 percent is nothing to walk away from. More important, however, even a brilliantly efficient stroke won’t do you much good if you run out of gas halfway down the pool. Training does have its place in the Total Immersion system, and the more you know about what the training effect is, the better you’ll know how to plan your own"
I thought about this and I read a bit more from Terry's book. I think there are 2 variables to this equation of swimming well in the triathlon. One is aerobic vs. anaerobic training. Here is a quote from the book:
"Conveniently, the way you should train for each event is much the same as the way you race it. Endurance training (longer sets, shorter rest, easier pace) develops the “wind” tank. Sprint training (shorter sets, longer rest, faster pace) develops the “speed" tank.
I think by becoming somewhat obsessed with SPL I turned my training sessions into short repeats which did nothing for my aerobic capacity.
The second variable is how to increase the distance without losing efficiency. Again as Terry says:
"To beef up your mile swim, your challenge is to add only laps or repetitions you can do with the same efficiency (stroke count) as your best laps, usually your first".
"So for the multisport among you, the bottom line is this: Since your smartest move in a triathlon is to keep your heart rate at 130 to 140 bpm for the entire swim, training at anything higher is a waste of time and energy"
However, I can drop my SPL but putting more power into the stroke but of course that has nothing to do with efficiency. So I think the SPL that Terry talks about is SPL you get when swimming with easy relaxed effort where SPL more closely represents how smoothly you move through the water and not how much power you put into it. And that will be different number for me.
Sorry I rambled on here, I was thinking as I was writing this and I think I am starting to realized where my error was. I need to set baseline SPL while swimming very relaxed and then try to hold THAT number while increasing the distance. Whereas before I would put a lot of effort into first few laps, which would give me a bit lower SPL but the one I could not hold it for long, stop it as soon as it would increase and thus get stuck with doing anaerobic sets.