Glad I tried it; doubt I'll try it again; some redeeming qualities.
I get a bunch of questions of the form: *jawdrop* You ran a game all by yourself?!?! I don't have a snappy response to this. Yes, I administered a game all by myself. But I had some vital help on the puzzle design from some expert playtesters. As for the one-man aspect... I don't think it made the game better. I think it made the game worse.
Like, if you have a choice between a one-person GC and a multi-person GC, go for the multi-person. (But if the choice is one-person GC or no game, then go for the one-person. :-)
Games benefit from multiple people. If it's just me designing puzzles, you get a bunch of oddly-constrained word puzzles. You don't get good logic puzzles, you don't get good art, you don't get nifty physical devices...
So why did I run a game on my own? I was working in Silicon Valley, living in San Francisco. I spent 2.5 hours on the bus each workday. After getting home from work, I just lolled around carsick for a while before going to bed. I didn't check personal email. I was thus pretty difficult to coordinate with—responsive on weekends, but not on weekdays. On GC, I'd check email after a few days to find drama: people wondering why I was ignoring their emails. If you let that stuff sit a few days, it escalates. Oy.
As long as I was running a game as an excuse to write an automated answer-verifying and hint-dispensing web site, maybe one person would be enough, right? As it turns out, it was.
I needed to pay extra-close attention to playtesters. A multi-person GC can go through a few rounds of "alpha testing" internally before showing puzzles to playtesters. There are thus more opportunities to experiment, to recover from failed experiments. I just had a few rounds of playtesters.
So the playtesters did some tough duty. They tested puzzles worse than usual—those puzzles had been unreviewed, untested. Fortunately, many of these playtesters were experienced GC folks themselves. They could suggest better puzzles. Their designs were really good.