Lott may have realized that actually fighting to save the bases was already a lost cause. Putting a hold on an action is often used only to delay an action, so the constituents may be told, "Hey, I tried my best".
In all the furor over the filibuster issue, I totally forgot the "hold" ability of the senators. Unfortunately, I'm pretty sure this also applies to judicial nominees, which really tosses a monkey wrench into things.
I think the senators are limited to one hold each on a particular nominee, and the hold will expire after a specified time. Seems that I remember there was an opportunity for one extension. What if senators can stack their holds, so, as one expires, another is placed immediately?
These were used rarely, and not for partisan reasons, IIRC. The bitterness existent now, IMO, means that the Dems have another tool available to frustrate the judicial appointment process. Changing the filibuster rules won't affect the Dems' use of holds.
Maybe that's part of the reason Frist has tried to negotiate the filibuster issue with Reid, and why Reid has been so arrogant in promising total obstruction. Could be a lot tougher than just getting 51 votes.