Like everything in tattooing - it depends. I've got well over 200 hours of being tattooed and rarely have any scabbing. I don't think I have any scarring, at least none that I can see or feel. I don't know if it's my artist, my skin, or my aftercare - probably a little bit of all three.
As to your artist, well known, tattooing for years, best in the shop don't mean anything. The only thing that counts is the final outcome.
I think you're probably stuck with just getting through this. If you aren't happy, don't go back. Realistically, what do you think is going to happen; you'll accuse him of being heavy handed and causing scarring and he'll say, "You're right, I'm sorry, I'll be more careful."