Of course there has gotta be a means to an end, here. Beppe obviously did not just sell our half of Berardi, who has been the more productive player AND has a higher ceiling than Zaza, for 10M, so that Sassuolo would allow Juventus the privilege of buying Zaza for "18M".
That cannot be what happened. Look at where this club is right now. Why would people think that our upper management is that stupid?
Management effectively lends them some money now, in a year where the club has a bit of extra scratch from our successes, and next year the number for Domenico is more favourable to us. Berardi continues to develop in an ideal environment, where he has been thriving, and they have a little extra money to patch the team up and prepare for more departures. They benefit, we benefit, Berardi is going to be a stud.
I rate Berardi, and I'm not convinced that Zaza is going to be a poor 5th choice striker. I think he'll work his socks off for the team, be a good teammate, and keep his mouth shut.
Anyway, we can't truly judge this deal until we see what happens with Berardi, imo. Then try to reverse engineer those numbers. Obviously there is a lot of trust between these two SDs, they've been working together for awhile, and I think this is creative accounting, pure and simple. Double-Co-own-Loan-option-with obligation.