No its not valid or viable. ITs heretical as he pointed out at least the fact that he doesnot believe Allah's pre-determination is absolute. Allah made Kharijites kill Ali r.a and Allah decreed 9/11. There is good in everything which happens to the Ummah. Ahlus Sunnah Muslims are perfectly comfortable in saying Allah creates evil. Allah gives cancer, AIDS, heartattacks, poverty and makes wars and bombs fall on our heads. Everything is predetermined is a basic Ahlus Sunnah belief. WE are not to question Allah's awareness or execution of destiny retrospectively. If he is saying that 9/11 happened out of the will of Allah that is completely heretical. WE have a clear well defined paradox in our belief which we as Ahlus Sunnah accept and thus despite believing that Allah does everything the believer does not cease to engage his nafs to change everything according to Islam's ethical and moral value system.