Another reason is that Level3 keeps dropping packets and doesn't seem to do anything to fix the issue.
I get more assists now, and have been colliding with planes more often because they warp around.
I'm seeing 30-100% packet loss and latency of up to 2000ms at the Level3 hop in Denver when I use Ping Plotter to show my route to HTC's MA.
I have called Comcast support, and they taught me how to restart my PC, power off and on my cable modem, and run their speed test, which shows that I have an amazing connection. Still, I was persistent in describing my problem with the Level3 hop and I had the issue escalated to the next level support, who I was promised would call me within 24-48 hours, 6 days ago.
I have read that Level3 does something called packet deprioritization, or something like that.