down-locking reel seat rods

My latest is a 6'6" 2wt. with a down locking slip ring. The reel is a Pflueger Medalist 1492ak.

It swings like a dream.

i believe that the reasoning behind uplocking rings were because as the rods got lighter the rods didn't balance well with the down locking reels being so far back from the handles. so they moved the reel seat up to compensate for the uneven balancing of rod and reel.
this is only my on thoughts but i could be just thinking too much
 
it could have been a ploy by the rod comp. though trying to sell you new rods saying that the up locking rods were more stylish and better or something like that.

Actually DT is partially rignt.  The goal was to move the weight of the reel just that little bit forward on the rod for balance.  Also, down locking seats have had a reputation for locking down too tight, and being hard to release.  Especially the rods with slip rings.  Two ring rods allow the reel to be moved to just about any position on the seat.  But they can come loose/get too tight if not checked.
       THe real movement to moving the reels was when we went from bamboo to composite materials. as the tips got lighter there was a need to move the weight to the front.  Some of the old bamboo rods were so heavy that they balanced with the old mechanical autowind reels on them.

The balance info already mentioned above is a factor in uplocking being more popular today by rod companies. The other factor is that they create a short little fighting butt by getting the reel away from you if you put the butt into your body for support. The reel can still turn freely this way.

I build a lot of down locking rods though because I like the way the look. They have a cool retro style that I love. Rod balance does not seem to be too far off with them. Here is a picture of one.