I've been thinking:) about your problem.
Since Bay's navicular problem is so slight, you could try this. Ask you vet how long the drug stays in his system. Some of them take awhile to get out. Condition him real good on the drug, take him off of them for that period then go on a 20 mile ride at the 4mph pace. and see how he holds up, with the pads and proper shoeing he may be fine. Then put him back on as soon as your ride is over. It's only been recently that they even allow pads, and one reason they do is for the horses that have problems like that but are still good horses. I've heard of some people who have horses with the same problem that compete.
As far as the heart rate, get a stehoscope and monitor it yourself, while he is on the drug, then while you have him off.
Becky
Can you give me some tips on how to post a reply on that yahoo group. I'd like to bump it to the top, but I can't figure out how. When I tried the "reply" area had your post and Bill's in it. Is that normal? My post just seemed to be attached to the bottom of his. Is that right? And at the top I noticed a warning about my e-mail address would be included. Is that OK?
Becky