This just happened to me too, almost a year after this post. I can’t believe this isn’t fixed yet.
Reading the zillions of random forum posts about this, It seems to mainly happen to new accounts, and many of the affected are people who have other accounts already established – ie, they know what they are doing, and what behaviors are acceptable. And yes, that means they’re more likely to mention people. BECAUSE THAT IS WHAT YOU ARE SUPPOSED TO DO ON TWITTER.
My guess is they’re using some kind of terrible algorithm that’s only looking at the expected new user’s behavior, as compared to yours, by comparing the % of tweets that contain an @, as opposed to actually looking at their content/value/spamminess. Pretty shoddy programming, if so.
It’s both embarassing for the seasoned user, and very harmful for new accounts in that tender new-growth phase as well, and especially confusing because it seems to decry the vary behaviors that made Twitter popular in the first place! Mentions were a user-created feature. Why would Twitter “police” them like this? Surely if it’s a failed spambot-catcher gone awry, they should have enough resources to throw at the problem to ensure a good experience by now? Or is all the effort going into copying every terrible aspect of Facebook?
** One actual non-rhetorical question: My following and follower counts appear to have been reset by this suspension. Did this happen to any of you? How long did it take for them to display accurately again? **