I look forward to what you think of brushing the rim with oil. Tom Lehman often tells of that if I remember right. Walter
Walter,
Yes, Tom Lehmann did discuss the application of oil to the rim of a pizza skin but it was to reduce the effects of oxidation, which would then reduce blistering. See, for example, Reply 67 at
http://www.pizzamaking.com/forum/index.php?topic=7740.msg65645#msg65645. If you read the comments of the poster at the PMQ Think Tank that gave rise to Tom's comments as reproduced in Reply 67, specifically, at
http://thinktank.pmq.com/threads/pizza-dough.6414/#post-42221, you will see that that the member did try oiling the rims of the skins and instead of getting more blistering, it was reduced. The same member tried using water on the rim, before refrigerating and before baking, and neither of those methods reduced the blistering.
If oil on the rim of a baked pizza causes blistering, then I would think that it should do so, perhaps in varying degrees, for any dough at any stage, from an emergency dough up to an overfermented dough. I once tried oiling the rim (half of it) in an experiment where I made a dough without yeast and the part of the rim with the oil did not exhibit blistering. I discussed the experiment at Reply 69 at
http://www.pizzamaking.com/forum/index.php?topic=7740.msg66521#msg66521. That may not be the definitive test since there was no yeast in the dough, leading to the possibility that oil may enhance or contribute to blistering if the dough has had some fermentation or some other condition that, together with the oil, leads to blistering. Also, my test was to see if a dry skin was the cause or contributor to blistering, which my test said no.
Peter