Years ago I did something kind of similar. I created my own Twitter client (never public and now defunct) but one of the features was that it would prevent one user from monopolizing my stream by hiding their posts after the three most recent. So say someone was live tweeting an event I would only see their three most recent, and after that it would display a collapsed bar to let me know it had hidden something.

Made skimming much easier, I still miss this feature.