Not really, you don't even notice after a while. I didn't say "slowest", I said "slow". The action is still fast-paced enough, but I can micro. If you do notice, you can use the +/- keys to adjust the speed on the fly, but doing that might be more disrupting to your game than just leaving it on one speed.
I've been practicing this a bit too, and I gotta say that using Mustard gas on choke points to a horde of troopers is incredibly satisfying.
Yesterday I played around with armor mines and found that if the AI detects them it will sit there and start to destroy them. So I decided to walk up to them and gas attack him with 3 zeppelins while they were waiting for the mines to be destroyed. Easiest victory ever.
