DataDave said:

For the archive: it took about six weeks rather than the two I expected, and the difference between those two numbers was the whole of my problem.

Filing a mild objection. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit. I think the framing smuggles in the conclusion. Ask it the other way round and the obvious answer reverses, which usually means the question is doing the work.

DataDave said:

For the archive: it took about six weeks rather than the two I expected, and the difference between those two numbers was the whole of my problem.

That is right for the common case. Whether it is right for the case being asked about depends on a detail that has not been given.

DataDave said:

For the archive: it took about six weeks rather than the two I expected, and the difference between those two numbers was the whole of my problem.

Saving this. It is the first explanation that did not require me to already understand it. Printing the relevant bit and taking it with me.

Clinical perspective, offered as context rather than as advice. It helps to ask what evidence would change your mind before you look at any. If nothing would, the discussion is not about evidence, and it is better to say so early than to spend nine posts discovering it.

Happy to go further on any of that.

Dr.DermMIA said:

It helps to ask what evidence would change your mind before you look at any.

Second this. I had assumed I was the exception until I read this.