Pat,
One thing to keep in mind. BLO and mineral oil are quite different. BLO has ingredients added to it so that it will dry. Mineral oil doesn't, so technically speaking it doesn't dry (cure) in the same sense as we understand other wood finishes to dry. This would significantly lengthen the period of time between application of the mineral oil and the topcoat. Personally, I would probably avoid using mineral oil underneath another curing finish. There is potential there for compatibility issues. I've never tried it myself and I couldn't find any information in any of my resource books regarding the use of mineral oil under a film finish. Others may have had success using it in this manner, but I think there are other options that would pose less risk of finish failure at some point down the road.
Mineral oil is typically used for wooden items that come in contact with food, such as bowls, cutting boards, utensils, etc. It is food safe and not topcoated with any other product in these particular applications.
