I agree. To each his own.

And be familiar with your cars. If in doubt, follow the carmakers recommendation. Coolant is only a part of the whole cooling system.

The cooling efficiency is calculated by the carmakers based on the 'totality of the cooling system design' of a particular car which should suffice even in harsher temperature conditions. I used to have 50:50 glycol mix exclusively and my cars run very nicely, though the cost is repulsive sometimes.

However, one cannot be really prevented to cool their cars according to their wishes, limitations, needs, or fancies. For example many PUJs here, use 'pure tap water', employ a larger capacity radiators, they remove the thermovalve even the radiator cap, but they add water frequently and it works according to their wishes; cost vs benefit in given point in time and situation.

With slower flow of cash, we may wonder if we can at least reduce the amount of the glycol coolant in the mix and IMO it can be done with precautions, without hurting our engines based on the technical facts and experiences.

You can even replace 'glycol based coolant' entirely with other additives and it will be just fine.

And please remember thet cooling sytem of our cars are prone to deteriorate as they old, to which standard fixes do not apply, practical, nor possible with the existing condition. In that case, do as you think right and be satisfied with it.

But please, don't put a joke in your brand new million buck car.