Withwine and I wrote:I don't think it really counts as playing it in that context. Obviously he's studied it and if not knowing all the play at least knows some soliloquies already, so he's probably said that on his own, or possibly in the company of Marwood at some point before.
Of course it counts... it's a movie. It's not as if Withnail and Marwood are real people living somewhere, and they "probably said" anything that we haven't been privy to. Whatever shows up on the screen, that we can watch, is what counts for the movie. Withnail said he intended to play Hamlet and then at the end, he plays Hamlet. It's part of the continuity of the story. Of course when he says he intends to play Hamlet, we understand he means to play it on the stage... and the writer and director of the movie makes sure that we see him play Hamlet - sadly, in front of a pack of rain-sodden wolves. It's the denouement. Withnail is going down, and Robinson chose to let us see that emotionally through his Hamlet performance, rather than physically with a shotgun.