I don't think seasoning has anything to do with sticking. I know this view is very contrary to "common knowledge," but I stand by it, especially since I've come to understand that the main reason for seasoning pans is to make them dark so they will absorb heat instead of reflecting heat.
The only time I've ever had deep dish pizza stick to a pan was after I seasoned the pan very well AND put a liberal amount of oil in the pan. Before that, I usually didn't grease the pan at all because it stands to reason that the considerable amount of oil in deep dish dough probably does the job by itself. I know deep dish is not the same thing as Sicilian, but I'd assume very similar natural rules apply. Also, I don't like the results when I use too much flour on a peel, so I have to figure adding flour to a pan creates the same unwanted results.