auto update TSS IF and other fields for workouts in Library based on actual performance
Planning is an integral killer feature of tp.com. As part of that, tracking changes in TSS and IF as CTL changes. That is, the TSS for one workout a year ago may not be the same today. Having the TSS IF (and even other values) adjust for workouts in Library would be very helpful in planning the effects of workouts when added to Calendar from the Library.

Check out our new Workout Builder. You can now create a structured workout in your library based on %FTP, see the calculated TSS and the actual power will be shown based on your current threshold once you drag it onto your calendar.
More info on our Workout Builder here: http://home.trainingpeaks.com/blog/article/introducing-trainingpeaks-workout-builder