How to Cook Oven Chips

This evening I was making the evening meal and was spreading some oven chips out on a baking tray when the following idea came to me. 

I always find it rather awkward to turn the chips over when they are half-done.  I usually manage to knock some on to the floor and forget which ones I have already turned over.  My idea involved using two identical baking trays:  Spread the chips out on one tray and then put this and the other empty tray into the oven so the empty tray gets hot while the chips cook.  At half-time, take the empty tray, turn it upside down and place it over the full tray, pick both trays up together, with the chips sandwiched between, and carefully turn them upside down.  Then take the top tray off, leaving the chips perfectly inverted in the previously empty tray (we did get one chip sticking to the top tray, but that was easily dislodged).  Then put the chips back in the oven for the second half.

I felt really pleased with myself for coming up with this idea, but Zoe, who was in the kitchen at the time, was not so impressed.  Still, the chips were nice, and Zoe ate all that I put on her plate.