No, if he's shit you'll hear how they knew it all along and everyone at Arsenal is incompetent/corrupt, and if he's half decent it'll be proof that everyone at Arsenal is incompetent/corrupt for not playing him enough. Either way, there'll be outrage and I-told-you-so's. Pepe was an exciting signing, he struggled for a long while at first, and began to thrive under Arteta. His game has significantly improved and he's finished the season strongly.
Credit or blame whoever you want, I guess.