> when you're trying to set a record swimming the English Channel
Your training time to competition time is about 99:1 (on the high side for the competition time). The record attempts (or the emergencies) are a poor continuation of this analogy when it comes to programming.
> unconditionally advising people to swim with weights, is simply bad advice
So we should advise them to use floats instead, since it makes swimming so much easier?
Yes, it does; but when you're trying to set a record swimming the English Channel, or escaping from a sinking ship you'd be an idiot to do it deliberately weighing yourself down with weights.
I suppose there's something to be said for both ways of doing things ultimately, depending on what situation you're in, and what your goal is.
...but unconditionally advising people to swim with weights, is simply bad advice.