Check this out...http://www.computrainer.com/html/coa...t-example.html

It does not directly address your question. I think one can see that without clipless pedals, it is impossible to achieve contant torque as discussed and measured by the trainer / computer. I saw a presentation of this system with a pro cyclist on the trainer and she got pretty close to perfect pedal stroke.

Edit: Bike fit and good pedal technique is an area that IMHO the 50+ gang can get a lot of bang for the buck and potentially reduce pain and fatigue. Loss of flexibility and and other problems of aging can be handled by repositioning and adjustments on the bike/ type of bike. The key is to find a service / guru that knows what they are doing. One may be able to get this at an LBS or NOT.