I didn't track, but I did try to alternate which boob I offered first, because both babies would feed a lot more from boob #1, and I wanted them supplying equally, ITMS.

All the same, one boob (lefty, AKA "Old Faithful") was the better producer, but I suspect I offered that side first a lot more, unintentionally ...

There also ended up being an entire cup size difference for quite a while after DS2, which made all my v-neck tops and shirts sit strangely until they settled back down, after DS2 weaned ...