I don't argue the idea that there is an optimum glove for each position, what I'm speculating about is how well the brain copes with using two different gloves that are relatively close to each other from day to day. Seems like you are working against your brain's ability to key into 'knowing' the glove as an extension of your hand. If you are going from an IF to and OF glove, that's a big difference, less chance of mental 'template' confusion I would think. But I wonder about the ability to mentally resolve a relatively small difference as successfully under pressure. The idea being that if you are charging to scoop a slow roller and your brain has got the wrong finger length dialed in -> probability increase for booted ball?