I played WoW on dialup will into the lifespan of WotLK. Average ping in the 320ms range. I learned to play around it to a degree, 'queueing' my spell casts by triggering it when my current one was close to completion, such that the command would hit the server about the time it would complete my previous spell. I could reliably chain cast spells this way once I got used to it, using the order of operations to my advantage as best as possible, as you say.
Once I moved and got onto broadband, and found myself with a miraculous 100ms ping, I basically had to learn the game all over again as my instincts would cause me to try to do actions I couldn't yet do, since I wasn't quite done casting a spell, harvesting a node, etc.
Later on I changed servers and was below 80ms ping, and the difference was again palpable but not game changing.
Once I moved and got onto broadband, and found myself with a miraculous 100ms ping, I basically had to learn the game all over again as my instincts would cause me to try to do actions I couldn't yet do, since I wasn't quite done casting a spell, harvesting a node, etc.
Later on I changed servers and was below 80ms ping, and the difference was again palpable but not game changing.