Of course they don't mention how annoying writing snippets can be (although I agree they are a good way for an individual to remember what they've done). They also don't mention that you can tell who is 'in' at Google and who isn't by the fact that they haven't written a new snippet in over a year.
Can you elaborate for those of us who aren't Googlers? Why are they annoying? If you write new snippets every week, how can you not write new snippets for a year? Is it the "in" people who haven't written new snippets for a year, or the "isn't in" people?
"Spent the morning trying to get the six people who care about serial numbers together to talk about the serial number issue, then argued with them for three hours over changing the return value of getSerialNumber to return 'None' when there was no serial number rather than 0 so that the machine database won't have several thousand machines with serial number 0. Argument against is that they will have to change their script to deal with a non-integer when the serial number doesn't exist."
Now your manager might not think that was so great, they might think you "can't get things done" because it took you all day and you didn't actually get a decision, the other 6 folks are pissed off because you slammed them in your snippet for being lazy, and you get slammed back for not being a team player. So you write a more 'friendly'
"Spent the day working on the serial number issue, not a lot of progress was made."
And now your manager complains that you are being so imprecise in your snippet that nobody can tell if you're working or slacking off. So you go looking for others who are nominally at your grade level and their snippet streams. You see either snippets like:
"Organized a summit meeting of key stake holders around our efforts to re-architect the serial number categorization issues which are have been plaguing SRE for months. Using the input received I've put together a comprehensive plan of action for addressing system wide issues."
Which is eloquently worded bullshit which makes young managers feel all happy inside but really doesn't say anything, or you see
"No snippets in the requested range, last snippet was xx/yy/zzzz (some year and a half to three years ago)."
You ask around and folks will say "Oh everyone knows what is up to." but you ask and say "Do you?" and they admit that no, they don't but its probably important, after all they've been here forever and they are a 'big cheese' in the system.
And of course if you point this out and it causes trouble for the 'big cheese' where it comes out that you asked their manager why they didn't seem to need to write snippets, well things would get really bad for you for a while. And its then that you note that what snippets 'are' is not at all obvious or useful.
That being said, I've always kept a note book and I write notes in it and track various projects. Its great to review and figure out what is stuck and what is making progress and it is wonderful to dump all the state into a single page or two so that I can work on a different project but 'swap back' into the stalled one just by re-reading my notes. Its exactly like keeping a lab notebook of your experiments so that when you go to write the paper all the data is right there. So I don't think snippets in general are bad, just that as a management tool they are easily abused.