After finding out (and detailing in a seperate post) that I had a couple of heater hoses on the wrong way round, I also realised that this meant the oil cooler had not been receiving a flow of hot water from the heater circuit, resulting in the oil taking quite a while to warm up.
I had also noticed that when driving the car hard and also at motorway speeds the oil was getting up to 110 degrees celsius. Which seemed a little on the high side to me.

After swapping the heater hoses around, I had a working heater and a flow of hot water to the oil cooler / heat exchanger.

I then gave the car a hard test drive and noted that the oil was not getting over 100 degrees celsius. Not a highly technical test, but it did show on a back to back test that the heat exchanger warms up the oil more quickly and then seems to reduce maximum oil temperatures by approx 10 degrees celsius.

I hope that this info is of interest to someone 😉