Lumbland appears to be turning into a rod nerd blog! never mind, this is something I've had in mind for many years. Which is the 'correct' way to fit a screw locking reel seat?
Old timers will tell you that the thread should go at the top, towards the rings - down-locking. Some time in the 1990s this lead to Berkley bringing out a range of carp rods with DNPS reel seats which were fitted down-locking. I believe on teh advice of Terry Eustace who was connected with Berkley at the time.
However, DNPS reel seats are intended to be fitted up-locking, with the thread towards the butt end!
The up v down debate has raged in fly-fishing circles as long as I can remember, with both sides having their reasons. It's less of a burning issue in coarse angling but it does crop up now and then. This is my take on it.
Back in the mists of time when all reels were centrepins rods were held behind the reel to allow finger or thumb control of the rotating spool. If a screw reel seat was use then it made sense to have the thread at the top so the angler's hand rested on cork. This gives a more comfortable and firmer grip on the rod. Today the same reasoning applies for use with multiplier reels if a trigger reel seat isn't used.
As fixed spool reels are held with fingers either side of the reel stem, to my mind, it doesn't matter which way round the reel seat goes as at least some of the hand will be resting on the reel seat. With a down-locking seat this will mean the thumb rests on the seat's thread, while with an up-locking seat the thumb will rest on cork. Having the thumb rest on a smooth surface is part of the design thinking behind DNPS reel seats, I think.
That's why, for me it's up-locking for fixed spool use, down-locking for multiplier use.