The Carmichael plan is good - it also works, as I've done part of a training cycle and definitely improved.
The only caveats:
- Powertap is recommended, as HR is a poor measure for the short intervals as it lags far too much for short intervals like 1min on 1min off. You can, however, use trainer speed to extrapolate power based on published curves for KK and Cycleops2 trainers.
- You'll be doing a lot of trainer time, as you can't really 'time-crunch' without cutting out hills and coasting. Typical weekday ride is 60-90mins on the trainer. This can get old quick if you don't like your trainer.
- You still put in real training time on weekends. A 2-3 hour ride on one weekend day and a 1.5-2.5 hr ride the other weekend day on average. It's not epic mileage, but for a typical racing roadie, that's enough distance to put some serious intensity and endurance in to improve at any level.