(Last post about C79. Earlier ones here
I think the major thing about Comiket, in the end, was seeing the level of skill and effort put into these things. People work on their doujinshi for months, you arrive at their table, flip through briefly, smile, and usually bow and walk away. (At least, that's what I did. I don't exactly have the killer instinct when it comes to retail.)
Perversely enough, I found it inspiring. You work hard, and your work evaporates, and you'll make something even better next year. I found myself really wishing that I had more time to draw. Thinking, perhaps, that it wouldn't be so bad to have a table at Comiket someday.
They say that people rise to the level of their peers, and I think that's the best thing about Comiket -- because it's so vast, the best stuff is better than you'd believe possible, and everyone there can see that and have something to aim for. Thus the average level improves and the cycle continues, with new cycles of aspiration as each seeks to outdo the rest, even if only by chance.
In the end, I didn't attend day 3, having been terrified by all that I'd read. I bought a random smattering of Touhou doujinshi on day 2, all-ages style, around 15 all told. (It actually makes a pretty impressive stack.) Not a huge amount, but it's media -- I have way more than enough to consume as is. And I'll be back, anyway.