You're right. There should be none. Three is not a lot, but it's three too many. The question is whether Brooks thinks three is a lot. Also, is Brooks including "cheating" where there was no intent, which technically wouldn't be cheating? I don't think Brooks should have made that statement unless he can explain exactly how he knows what he's talking about. If you're going to cast shade, be prepared to back it up.
My instructor is really high on the Edel putter fitting system. Now it could be that she teaches at a facility that is also a certified Edel fitting center, so she has some bias. But I don't think this is the case because she is always very honest about other fitting questions I've asked (i.e., told me not to buy shafts from them, gave me affordable shaft options with the characteristics I needed, and pointed me to eBay).
The way she explained the putter fitting was that it customizes every aspect of the putter to match your putting technique. I assume this is possible at another fitter, but the Edel system is designed for this type customization (alignment marks, head shape, weight, hosel, loft, etc.), while maybe other putter manufacturers are not.
Reread 4.2, it certainly provides the answer.
It doesn’t say when you cannot apply the heat. It just says you cannot make a stroke at a ball that has been heated so as to deliberately alter its playing characteristics. It could be immediately before the stroke, or 2 days before. The rule doesn’t care about the time. Only whether or not you did it.
People are really over thinking this one...
I see a lot of people using it, they never complete the swing, go to A10+, guess the band makes that practically impossible? I've only used the short green one, I guess the longer one is more forgiving but using on longer clubs. Also, how do you decide on where to clip the thing? I opted for closer to grip, didn't want too much tension.
A little off-topic, but this: