Not really.....was always frowned upon due to the slight differences between any two pairs, no matter how close you get the cleat set up, etc, etc. may cause problems. Plus both pairs would have to be same brand, same model.

I had a pair of Tecnos and Genius 3 going at one stage....only coz the 2nd pair were "warmish" and cost about $50, no questions asked.


Short answer is no for bike racers, but would pose no real problem to the majority.

Just buy the new pair and keep the oldies for rides in the rain or a fallback pair.