For me, the writing of comments is part of the thinking process.
In effect, you are using prose as a form of pseudo-code.
In the past I've tried or used prose, Weiner-Orr Diagrams, Yourdan, SSADM (and derivitives), Jackson, UML, various flavours of Case, and half a dozen variants of pseudo-code to plan code and/or document it. Some with more or less success than others. But in the end, I've found that the language of implemetation is the best pseudo-code (for me!).
I'll often start by sketching out the skeleton of the algorithm in Perl-glish (or C-glish or whatever-glish), and then slowly refine that into code. The advantage is that even at the early stages, I can use the compiler or interpreter to check my progress. When the compiler stops complaining, I'm usually getting close.
it's not the most significant of the comments in a 2,800-odd line module.
Agreed. And it is perhaps a little unfair to pick out so few lines from so many, but to do more entails a lot of work. I did make a start on attempting to re-write the entire module in what I would consider to be a self-documenting style, but then realised it would be equally unfair, as I would be starting from the position of your working example. I also ran out of awake cycles.
The bottom line has to be that there is no 'one right way' to program. But historically, I've found that people tend to be even worse at writing good comments than they are at writing good code. The difference is that I have the compiler to help me sort out the code, but no assistance is available for comments. (Especially a problem for me if they are in German or Italian or Chinese or Spanglish :)
I've personally found it more efficient and effective to put a little more effort into chosing variable and function names that allow the code to be somewhat self-documenting, than to write everything twice. But I realise that that doesn't do it for everyone.
But I do take exception to the implication that my deliberate and considered preference for minimal commenting is born of laziness or a lack of consideration; as nothing could be further from the truth.