I am seeing lower latency values after installing Leatrix Latency Fix, however, I'm now experiencing lag spikes, especially during periods of frantic activity in dungeons. Why is that?
The increased frequency of acknowledgements may have caused your routers buffer to fill up (essentially creating a traffic jam). Very few people have reported this problem, but it's more likely to occur when you have more than one computer on your network, you are running software which produces lots of network activity or you're connected to a wireless network. If possible, try using a different router with only your computer connected directly to it and don't run network intensive background applications while playing (such as P2P or voice comms).