[jasode]

I can't debate what some perceive as costly because it's an honest reaction to reading some forms of text.

In my case, all lowercase and lack of punctuation don't bother me or slow me down. (I'll agree on uncommon acronyms hindering understanding.)

To reduce some frustrations... listen to linguist McWhorter explaining that people should think of texting (or Slack) as "transcribed informal speech" -- instead of formal writing.[1]

That said, the author Mitch Lee's bio says he's a cofounder of Penny. If you are employed by him and are communicating at his company via Slack, it's better for your career if you follow his guidelines.

[1] https://www.youtube.com/watch?v=UmvOgW6iV2s

[comeonseriously]

>listen to linguist McWhorter explaining that people should think of texting (or Slack) as "transcribed informal speech" -- instead of formal writing.[1]

I can't watch the video right now, but even in informal speech, I hear periods and commas. I think that those are necessary for communication. Not including them, as I mention in another comment above (or below?), induces a cognitive load on the reader. Nobody should be asking for perfection on Slack, but mostly correct should be the bar.

[djur]

Sure, commas should be used when grammatically necessary, but a period before a newline is not going to make a big difference one way or the other in terms of cognitive load.

[bccdee]

no

you hear pauses, which can be communicated in more than one way

as shown here

...was this unduly hard to understand?