Hi Chuck,
I asked the leather chemists once a question about Aluminum stearate in leather conditioners, and here is an extract from their answer to me (so it seems it is bets just to let the leather stay acid):
Aluminum stearate is just soap, though most would probably consider it more a grease than a soap. It combines a wax and humectant roll, but just as most leather experts warn against the use of saddle soap, I think you will quickly see that this soap really has little to offer your mix. The biggest issue with soaps and leather is that soaps are made under highly alkaline conditions, and unless that basicity (alkaline pH) is neutralized it can carry terrible consequences to the acid leather.
I hope this helps!
JOhan