Expressing that you have no idea what the other person is saying (but that this is part of the value of this community) is not without substance or useless. They could have been more verbose about it, but I'm not sure that makes the community better.
The guidelines are guidelines. We all work to interpret them. HN themselves in introducing the guidelines says that "empty" comments can be okay if they're positive, which I feel this was.
Fair points, and I'd appreciate a source on your last statement from the HN guideline side. I just reviewed them to take into account more nuance that may have been added since the last time I checked. I will disagree with your interpretation of substance but defer to the guidelines.
> The test for substance is a lot like it is for links. Does your comment teach us anything? There are two ways to do that: by pointing out some consideration that hadn't previously been mentioned, and by giving more information about the topic, perhaps from personal experience. Whereas comments like "lol" or "That's the dumbest thing I ever heard" teach us nothing.
> Empty comments can be ok if they're positive. There's nothing wrong with submitting a comment saying just "Thanks." What we especially discourage are comments that are empty and negative—comments that are mere name-calling.
The guidelines are guidelines. We all work to interpret them. HN themselves in introducing the guidelines says that "empty" comments can be okay if they're positive, which I feel this was.