Oven had not been that effective recently, kept going out, flame not constant. (now suspect flame wasn't in line with the thermocouple thing)
Read on here about the flame spreader could be worn/damaged. Took the flame spreader out and gave it a clean around where it is located in the oven base. It looks as though it may have been bed in with some sealing compound. Would this be correct or should there be a fire proof washer like on the hob.
To be honest, I don't think it has to be embedded in anything if it is fixed properly ie, screwed down because it is only controlling the action of the flame on the thermocouple. The 'sealing compound' may even be years of accumulated crud? However if you have any doubts at all, be on the safe side and consult an expert.
Dave
------------- Give a man a fish and he will eat for a day,
Teach a man to fish and you can get rid of him for a whole weekend.