I'm feeling the same about friday - I missed Portishead at ATP but Aphex was craazzyyy. I've read that RJD doesn't like doing live shows it kinda came through.
As a consistent coachella goer, I will not be going all 3 days this year unless they improve Fridays lineup, last year Friday was amazing, Bjork to close it out was a great performance and showed some interest in new instruments, but jack johnson? If I wanted to hear some guy talk about beach nonsense I'd go to an NA meeting in the South Bay area. As much as I enjoy Portishead, I feel Aphex Twin is missing with them as they did All Tomorrow's Party together and those were the two acts I am dying to see. The sound for Portishead will be amazing at Coachella, hopefully surpassing NYC Live (amazing album go download it (i mean lawfully purchase it) right now).
On the bright side Jack Johnson and Emo for Deathcab will bring it hot girls.