Hmm, so I should mention that I have ZERO experience with ovens and baking! Until a few hours ago, I thought the paper I used was a baking sheet and only after googling for info on the stone-paper relationship did I realize that such a thing as parchment paper exists :p (still don't read Dutch!) I grew up in India, cooking Indian food, and we just don't bake! I bore you with this story because it leads me to a new question:
Is it bad to have parchment paper in an oven that gets too hot??!! Am I going to die of cancer?!?! Or have my oven explode?!
As for 450C, my Trebs oven ( http://www.amazon.de/Trebs-99229-Steinofen/dp/B00DK6T034
) goes to 400C unmodded, but even after one hour pre-heating, it was not browning the crust much after 5-6 minutes. I ended up exposing the thermostat (pulled the knob out) and turned a fan on high towards it, and suddenly the thing does not cut off at all. I am very sure that the oven goes well over 450C now, evidenced by the second pizza on this 'enhanced oven' that ended up with a completely burnt crust in 45 seconds flat! Without an IR thermometer, I have no way of knowing the actual temperatures, but I guesstimated 450C based on the roughly two minutes that last pizza took to make.