I have been having a major issue with lag in the game and naturally, it always spiked right when I entered PK. Of course, nobody would seriously believe this but I finally found out what was wrong, some odd years after it started.
I had always assumed it was because I have been living abroad, but that wasn't the case. Recently, I started to notice a pattern with incoming text and lag. When the MUD ouput is high, my lag is greater. It would take two rounds to look at someone and run by. Fighting a necro would mean I would be lagged to death by the text spam.
Once I understood this, I went through all of my zMUD preferences and started playing with things, but nothing worked. Finally I searched the internet and all mightly ZUGG himself provided the answer.
My problem was not because of any lag but because my scripts were checking each word for triggers. When I cleaned out everything and played vanilla, I had no lag at all!
I looked through my scripts and found the culprits: my cabal triggers. I have scripts to check the who list and record what person is in what cabal and to color them on my wheres and so on.
Over a period of something like nine years, these variables got very big and it was checking each incoming word from the mud through each cabal member list to see if they should be added or colored. This created lag on my end. The more words, the more lag and frequent disconnects.
I disabled these scripts and now I absolutely fly. Almost no lag at all. Freedom!
So, if you are having lag problems, check your scripts.
After several years of heavy PK lag, this is a very, very, very welcome change. 
