Spam filters "care" about HTML comments embedded in an email message?

I'm rebuilding an email notification tool for the office's clients. The tool will send 20 to 50 emails per day to email recipients outside our domain. Subsequently, "playing nice" with recipient spam filters is important. Trying to keep the HTML/CSS under the email reasonably simple, I'm basing my emails off Sean Powell's emai_lite.html boilerplate shared here: GitHub Repo. Sean makes a comment in the repo README.MD file that strikes me as odd.

DO NOT COPY OVER COMMENTS AND INSTRUCTIONS WITH THE CODE to your message or risk spam box banishment :).

Is Sean implying that the presence or lack thereof of HTML comments in email_lite.html can affect how the incoming email is classified by the receiving spam filter? That seems weird to me.
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Mal OsborneAlpha GeekCommented:
There are a HEAP of seemingly innocuous things that can add points to a spam score and see your emails sent to some oubliette. A subject in all capitals,  more than 6 recipients in alphabetical order, and  keywords such as "lots of money" can all cause problems. I have 2 suggestions:

1. Ensure you have reverse PTR and SPF records correctly set  up.  This will help a lot.
2. Test your email by sending to an online spam checker first. The one below is good:

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