From my personal experience, yes Clear performs traffic shaping. I should have gathered data while I experimented with the throttling issue. The bandwidth issues I saw with Clear were throttling Bit Torrent traffic directly. This was easily mitigated by enabling forced encryption on the Torrents.
Clear users are seeing the throttling put into place when they exceed 7-10GB transferred in a month. However, I did not see throttling when I exceeded 10GBs. Total bandwidth usage cap seems to be a new issue.
Bandwidth throttling maybe a serious issue for Clear users. For example Comcast has a soft cap of 250GBs a month. This is more than enough for any user, even heavy bandwidth users. The Clear cap is too small for the modern household.