Latency remains in effect regardless of macros. There's no getting around that unless you have some ungodly low ping to the servers. From the few games that support this type of feature, you have to have pretty low ping to make use of a macro, be it third party or not, in order for it to work well. If you had say, 20ms or less ping, you could probably get away with using macros reliably, but we all know that's a very small portion of ffxiv players.