Not necessarily...I think it would depend on how much Atletico were offering upfront as a payment and how much they wanted to pay in installments. As we are a cash rich club, we have been able to offer more money upfront for a player - this approach helped us with Ozil as Real needed money to be able to pay for the Bale deal. Napoli may accept a lower transfer fee if the bulk of the money was paid upfront to enable them to invest in their squad. Also the whole player plus cash deals, particularly when there is more than one player involved is very complicated which is why hardly any deals like this are done.
In saying all that Napoli are c&nts when it comes to transfers...but it would be interesting to see whether the club stick to the whole pay the full release clause or not. Higuain only has 2 years left on his contract and his value will go down massively over the next year. The club may just accept that but I reckon if enough money was on the table before the end of the transfer window they would do a deal with us. And I wonder if this is us just being sneaky again in the transfer market and waiting for the opportunity to make an offer towards the end of the window - high risk but may mean we get Higuain at a fairer price!