ill take the points and not lose three hours of my life being droned on at about doing 26 in in a now 20mph major A road, these 20MPH zones, LTN's and the like are a farse, driven by cyclists with clip boards who contribute zero to poy for all the stupid ill placed bike lanes.
Actually, i wonder if the mamil's will abide by the highway code of not overtaking on the left now they can actually go faster than a car is allowed to. 
Seems a pity that you should decide unnecessarily to accept 3 points because of a couple of falsely held preconceived notions you have...
As I explained previously, I attended a course last year and found it rather helpful with no droning and no talking down and not at all an inconvenience. You might have found that attending one would have been quite informative if you drive for a living. You might have discovered, for example, that a 20mph limit doesn't necessarily have to have roundels on the road.
You also might have learned that 20mph limits have nothing to do with cyclists and rather a lot more to do with extensive scientific evidence proving that 20 mph limits significantly reduce the risk of serious injury to pedestrians.
But of course you don't want to know any of that...