Secret codes and rationalizations

I'm still trying to follow the Chris Carmichael Time Crunched Cyclist Training Program. I'm doing pretty well. I even managed to get in a set when I was in Morro Bay. But sometimes there are ... issues.

Today I was supposed to do over/under intervals. Carmichael describes them as dividing intervals into sections of 92-94% of your maximum sustainable heart rate with other sections at full-tilt 100% plus.

In the book the description reads:
60-90 min EM with 3x8 min
OU (3U,10) (6 min RBI)

Which was making me crazy. What does that "10" mean? After entirely too long — I mean days —  I finely realized it wasn't "one-zero," it was "one-over." So: Three minutes at 92%, One at "crazy," then repeat. Do that three times. So I did. You can really see the "crazy" parts in the graph.

The graph ends up interesting because the heart rate lags behind the work done, i.e. it takes a moment to ramp up, then a bit to wind down.  That must be why people spend big bucks on power meters.

Is it time to start the rationalization machine? Is a power meter really that expensive, considering how much they do, and how cool they are? And because I don't go to Starbucks and buy a fancy coffee drink every day I'm in effect saving all that money that could go to a device that would only improve my health, making me a happier person, which would benefit every single person I come in contact with.