“then why does the rule revert if the Democrats lose control of the Senate?”
It does?
I've looked over today's Congressional record and don't see the vote or details:
http://thomas.loc.gov/cgi-bin/query/B?r113:@FIELD(FLD003+d)+@FIELD(DDATE+20131120)
And I've looked at the activity today:
http://www.senate.gov/legislative/LIS/floor_activity/11_20_2013_Senate_Floor.htm