Running

That's sort of what I'd thought: rather than declaring it to be the solution, throwing out my shoes and switching over, I considered getting some minimal shoes and doing the odd short run in the park as a trial.

I like the idea of varying runs, just as I vary bike rides.

I think its quite common to use them for quicker shorter runs. Then use your shoes of chioce for the mile munching. I tend to have 4 pairs of running shoes on the go. It get a bit like the bike n+1 thing. My excuse is the varying trail conditions, and varying tarmac miles.

If anything they make you feel fast. Like when you climb off your commuting bike, and get on your weekend roadie.