Hi,
* I wish to experiment with dough that has olive oil inside. I used to make it on my regular oven and the taste is very good. should I count the oil as % hydration?
We generally include oil in the hydration in France (maybe Italy as well, I'm not 100% sure), but I asked once Tom Lehmann what he had to say about it, and his reply was that oil and water have different roles in dough so they shouldn't be counted together. I've been separating them since then!
* should dough with Olive oil be baked at lower temperatures, or will it work on the higher end just like the oil-less dough?
The question should be taken from the other angle: do lower baking temp need oil? And the reply is.. yes. In a nutshell, oil keeps moisture within the crumb so it's interesting for longer bake/lower temperature bake; when baking at high temp (I'd say 450°C and above), pizza bakes in one minute, there's still a lot of moisture, so adding oil would lead to keep even more moisture in the crumb (which would result in an under-baked crust).