I understand that lag may have come around when the TFU update was released, but I highly doubt that the TFU update is the cause. There have been many bugs since it come out which I'm sure are already being worked on, however lag is not one of them, I don't think changing how a system works would cause lag to the server as all your really doing is just taking the option and putting it on a different NPC.
With all due respect I think your incredibly wrong.