Concept 2 is a little different in that you're not dealing with wind, gradient or surfaces. So while the relationship between pace and power isn't linear it is at least consistent from one session to the next. Plus the display isn't capable of showing both pace and power at the same time (or at least not on the ones I've used), so given you have to choose one or the other it makes much more sense to pick pace since that's what you need for tests and races. I did have a coach ~20 years ago who used power to work out intensity for different athletes and sessions, but he always translated it back to pace to make it easier for us to follow. Suspect that sort of approach is probably more widespread now.

Agree there should be no objections to using running power. Does seem to me though that it would be less useful than cycling power, given that speeds are much lower (so wind has a lot less impact and gradients change more gradually) and there's no gears to take into account, so RPE and pace work a lot better. Not perfect, but good enough that I don't think running power is going to change training approaches as much as cycling power has.

Before you purchase a stryd foot pod, know this … My stryd is less than two years old and won’t hold a charge. When I contacted stryd to get the battery replaced, I was told they couldn’t do that and that I would have to buy a new foot pod. However, they were “generously” going to give me a 35% discount on a new foot pod. I asked them “Why in the hell would I buy a new one when you guys wouldn’t even stand behind my current one?” I’m not saying everyone will experience the same battery issue I am experiencing, but you need to be aware that they do not have a good system in place to address that situation when it does occur. It’s just incredible to me that they can’t swap out a battery and charge me some fee for that instead of requiring me to buy a whole new unit. Incredibly disappointed in their customer support.

Not disputing that your experience with Styd customer service hasn't left a bad taste in the mouth, but I don't think replacing the battery is a great solution. For sports tech (especially an item likely to experience repeated immersion like a foot pod), dust and waterproofing is a significant and important issue. It's difficult to ensure proofing seals remain intact when replacing the battery on an existing unit.

While it might have been out-of-warranty, good customer service should certainly have come up with a better offer than just 35% off. After all, I am imagining that the cost of materials of a Stryd unit is pretty small, and the real cost is the R&D behind it. I would have thought a fair offer was you paying the postage on a replacement unit, or given the latest Stryd is new and improved and allows for wind, perhaps $50 for a new unit might have been fair too.

Yeah, I agree that battery replacement could be problematic. I would be perfectly happy paying $50 for an old unit without the wind measurement. I am not looking to better my situation, just continue using the version I bought.