Why would Mourinho take Higuain when he kept him on the bench at Real for the majority of the season
Simple. The most important player was ronaldo, as illustrated in the 2011/2012 season where he was better then messi. (europe, classico's, national team, la liga)
But the formation Mourinho wanted to suit Ronaldo, involved a 4-2-3-1, with the striker mostly beeing an working assist/buildup bot. benzema is supposedly better at that then Higuain.
However, take away the Ronaldo factor, and think about his time at Inter, where he had Milito. Mourinho allways praised clinical strikers. Hence Higuain wanted to leave after 2011/2012 because not playing despite seriously outperforming benzema. But Mourinho plead him to stay.
So dont count that out, altho Mou is very likely to want a physical eto'o type striker again. And there is cavani.