As I type this my wife is making a mess of the oven I spent ages cleaning
last week. She is roasting some pork and it is spitting all over the place.
I suggested she put foil over it but she said 'not yet, do you want it
nicely done?" So I backed off. Noticed some cooking oil and asked if she had
added some to the roasting tin - she claimed to have used just a bit to stop
it from being too dry. I started to wonder about the effect of vegetable oil
and animal fat in one tin - could this cause spitting?

If I pluck up courage should I make any suggestions - or just enjoy the pork
and then roll my sleeves up and clean the oven.

It is electric with a top and bottom element (Might have been better in the
fan oven)