I'm trying to translate the following quote from Dürrenmatt, for the article I'm working on:

[A]uch ich habe eine Kunsttheorie, was macht einem nicht alles Spaß, doch halte ich sie als meine private Meinung zurück (ich müßte mich sonst gar nach ihr richten) und gelte lieber als ein etwas verwirrter Naturbursche mit mangelndem Formwillen.

I pretty much understand what it means, but I'm having trouble with the second clause ("was macht einem nicht alles Spaß"). Those of you who know German very well (and are preferably native German speakers): What's your take?

UPDATE: Thanks, all! My preferred translation, which I'm including in my paper, is the following:

I too have a theory of art—what doesn’t one do for fun?—but I keep it to myself as my personal opinion (otherwise I’d actually have to follow it) and prefer to be considered a somewhat scatterbrained nature-boy with no sense of form.

Feel free to keep commenting if you like. I'm adding acknowledgments to "commenters on the Volokh Conspiracy blog" to my paper, but if you feel you want a more specific acknowledgment, shoot me an e-mail.