What do you mean by Twitch's bandwidth cap? Obviously Twitch supports more than 100 viewers, so is this an upstream cap from the streamer or a downstream per user cap or something different all together.
A glace over Twitch's broadcasting guidelines was not enlightening, but I'm clueless in these matters.
If you send more than about 6.75mbps of video to Twitch, you'll start getting errors. With the variable size of encoded streams you need to play with the cap a little to get a problem-free experience.
A glace over Twitch's broadcasting guidelines was not enlightening, but I'm clueless in these matters.