Thanks for all the feedback. I'm sold on continuing interval training through the rest of the offseason. In addition to the responses here, I found some good information on a program design linked to trainer David Morris (http://ashwinearl.blogspot.com/2005/...index-and.html) that advocates a reverse periodization approach. This makes sense for my situation with only 4-5 training hours per week. I added back interval work last week and with just 2 days of it, already noticed significantly more snap and ability to go deep multiple times in my 2hr Sunday ride yesterday.

My concern now is how to schedule 2-3 days of bike interval of training with 2 days of strength training so I don't overdo it. I've found squats and deadlifts to be incredibly helpful for climbing power, and strength training in general to be indispensible for overall fitness, so plan to continue lifting year around.

Current plan is:
Sun - 2-3 hr group ride: Mix of Zone 2, hills, and tempo
Mon - Strength: Max effort (3-5rep) Bench, Rows, Overhead + Explosive squats or deadlifts
Tues - Intervals + 10-15 min low cadence effort for neuromuscular endurance within a 1hr total ride
Weds - Same as Tues with slightly less intensity
Thurs - Off
Fri - Strength: Max effort (3-5 rep) Squats or Deadlifts + High rep (10-15rep) bench, overhead press, rows + pullups
Sat - Off or Zone 2 ride