Geodata on or off doesn't make a difference for me. Mayyyybe it's a little better without geodata, but not really sure, probably just placebo... it would be very hard to measure a difference
As seen in the video below, if the monster is moving right before I attack it then there is very often 0 delay (sometimes you slide a bit in the direction they're going). If they're stationary for some time then there is 100% chance of delay, especially if I'm out of range and have to first run to range to be able to cast/attack. As if their location wasn't up-to-date in the client.
Tried comparing my /loc and the monster loc using info (shift+click) but I'm probably too dumb to make some sense out of it...
What is funny is when getting the monsters loc this way, the delay never occurs. Probably because by getting it's location it actually gets updated?