Normally 2 coats does fine for me. Although at times, one coat applied with your fingers or palm does the trick and the bat doesn't need anymore.
Out of interest, how does everyone oil their bat? With their palms or with a rag/towel/tissue? I tend to use my palm and fingers when the bat is brand new, as it needs a little more oil, and then I start using a towel or rag for the other coats as they can be thinner. If I am not scuffing up my bat, I tend to clean the face every week or 2 using a towel which has been used to oil a bat. It is really to clean away any dirt, and to keep the face sealed. I find that this works well, as my bat still performed really well, and despite having quite a few cracks, lasted me quite a while (was an Adidas Incurza when they first came out) and I just sold it on Sunday.