I just tried to use the bracket escape codes to show someone how to post a comic, and when I previewed my post, the comic showed up. I'm going to test it here. First example below is just posting a comic. Second example below is using the escape sequences. Third example below is using the escape sequences and escaping the ampersands as well.
Wild hypothesizing: does the parser turn escapes into brackets before turning bracketed tags into comics? If so, maybe the escaped comic tags get turned into real comic tags and then the real comic tags get turned into a comic. Making conversion of escape sequences to brackets the last thing the parser does might solve the problem.
--- The what mentioned above is total fiction. Please don't take it seriously!
I will take a look at this soon, I messed around with some things while I was in there a week or two ago. Maybe I broke something.
One thing though, you no longer really have to use the comic tags. You can just post the URL of the comic and it should work. I'm just pasting the URL: