I do not weave that much in Boston. Drivers here are rude, drive really fast, do not pay attention to traffic signs or rules of the road. They will try and kill you with there car if you cut ahead of them. This also goes for city bus drivers, who never signal before moving back into traffic and even if they do see you...they do not care, they do have a schedule to keep.
And even if you ride in the bike lane, shit like this happens