Ask yourself – did you really understand what the hell was happening in Inception sober? If the answer is yes, you won’t get anything out of it while high. If the answer is no, you sure as hell will not have the slightest idea what is going on if you do watch it while high. And if the answer is you don’t know because you’ve never seen before, you’ll be completely wasting your time watching it high as you will be lost entirely after about 30 seconds.