Yeah, it's not leakage in the traditional sense like when you get blue smoke from ring blow by. Every motor oil has seal conditioners that keep the seals from drying out. There is a difference in the amount or type of conditioners used in Type III or Type IV synthetics and dino oil. Please don't quote me as to which one it is, I can't remember anything other than it's different. Search through the BITOG site if anyone cares that much. So yes, using a blend of dino and synthetic can mitigate this temporary oil usage.
However mixing any two oil brands is not the best idea unless you are an oil industry chemist, or have access to the advise of one. The base stock oils are completely compatible between dino and synthetic, but the chemical add packs (which are extensive and voluminous) are likely to be very different between any two motor oils and can easily clash, greatly reducing performance and/or longevity. Or there can be no problem at all, it's just that you don't know unless you know what you are mixing together.
