After coming back from a break over Christmas I discovered that when casting spells with "long" casting times, there was a strange lag/delay where the next spell would start casting about half a second before the current one finished casting. It wasn't like this before the holidays, and I haven't changed any settings. It happens for Healing Wave and Chain Heal, but not Lesser Healing Wave on my shaman and Greater Heal but not Flash Heal on my priest, which leads me to believe that maybe it isn't due to my internet. Also, it doesn't happen on other servers with any spells, long or short cast time.
I've tried downloading a completely new client from the Warmane site, with no addons or changed settings, and it still happened. I've also tried changing my DNS with no improvement. In the video below I have Quartz enabled to make it easier to see the issue, but all my other addons are disabled.
Strange. I know this is a long shot, but is there any way for me to disable it?
It's really annoying, as when casting spells one after the other, I have to decide on a spell rank and target for my next spell 0.5 seconds before my current one stops casting. It's very annoying to say the least.
As far as I know, it's not possible to disable it. You don't have to decide next spell 0.5 seconds earlier if you don't want to, you just can't change your mind if you already pressed a spell within those 0.5 seconds. But some changes in your play style might be needed if you want to do it that way.