Man, we overanalyze these tips until they sound like a science project. From what I've seen, a cool rinse for around 30 seconds makes a difference for most folks, but ice cold isn't necessary. Curly hair tends to show more smoothness, but even straight types get less frizz. Just don't blast your scalp with freezing water unless you want a shock to the system.

Honestly "runs fine without" is true for most daily driving now, but pushing that logic too far can bite you. Like if it's below freezing and you immediately floor it, that thick oil isn't protecting anything. Or if you only take two minute trips, the engine never gets to temp and it gunks up over time. It's less about a five minute ritual and more about being gentle for the first minute or two when it's really cold out.