You can skip the rate limit by connecting directly with the IRC server. Using some script servers like mIRC will cause the rate limit because there is a pause somewhere in the sending of the data.
If you can constantly stream data to the IRC server, there is no rate limit. This is how these bots are flooding channels. The only time you will see them drop is when there is a major packet loss from there end. This is how they create view bots.
To control those bots, you need a verification of actual viewers versus actual people connected to the Twitch IRC API. This is a very stupid design from my point of view. So one IP address can create thousands of users. Please fix this twitch!!! Allow only a limited amount of accounts from one IP address and you will stop a significant majority of view botters.
But in order to control the chat through moderation, you have to have a separate program connected to the IRC server that would handle all the chat commands coming through the channel. The twitch chat servers can’t handle all the API’s running then moderators trying to do there job.
IMO, if Twitch would limit IP’s, moderators would have it extremely easy 