how can they insist on you buying a heated screen if presumably at the time the car was purchased it was not possible to install heated screen?

The problem is the staff on the parts counter who will know a current very expensive car like the backs of their hands but will know little about a 27 year old much simpler car but still insist that you need the same parts.

When I bought my first Caterham there were no heated screens thus there is no loom/switch in the car and unless you are experienced electrically no way to fit one.

When I bought the 2nd Caterham the heated screen was a sensibly priced option so I ticked it. Driving with the hood up on wet days caused much screen demisting and with no air vents to the screen constant wiping is needed. The heated screen helps but its not anywhere near as efficient as the screens we have had in Fords. Best solution is to wear suitable cloths and not fit the hood. Mine was last up in 2007 on the way home from a Track day but only to keep my kit dry(ish).

Looked in the MOT regs and I can find nothing about windscreen vents and heated screen thus it seems the bloke at Caterham is simply trying to up-sell their products. In 30 years of having Caterhams MOT'd I have never seen the tester check the operation of the heated screen or make an advisory about the lack of vents.

If I’ve read correctly, your current screen is heated, but to save money on the insurance excess you would rather have one without the heater? Surely the £50 difference between the heated one supplied by the insurance company and the non heated type if you sort yourself, is not a big enough difference to miss out on the heater. Or am I missing something?

You are correct. But its not a money saving exercise, its a simple fact that since I have not fitted the hood since 2007 I have not needed to use the screen heater. That and the fact that when you use it there is no way its as good as one fitted to a Ford.

Another consideration is the visibility of the heater wires on a misty morning, very distracting.

Its something I will never miss.

But good news. The Auto Windscreens chappy came today and as expected his device would not fit over the chip because of its closeness to the frame. However, all was not lost. He produced a smaller device which very nearly fitted and then produced what looked like a dentists drill (it was actually a dentists drill) and made a small hole (about 1mm diameter) in the outer layer 4mm from the chip. He then injected the resin down the new hole (his device fitted now) and the screen is repaired with no evidence of the original chip or the hole he made.

All for £0.00, they have even e-mailed me a copy of the invoice.