I played for the first time last night after the spam filter change. It's pretty bad...
I was cav and I yelled to my allies to open the gate a couple of times and was immediately muted. Ten seconds later, I spotted a couple of throwers that my allies didn't and tried to whistle to get their attention... you can probably guess what happened. I ended up having to just run them over instead, also running over an ally that was in front of them that didn't see them, and losing hp on my poor horsie to their throwing axes.
Seriously, nerf this shit. It shouldn't mute you if you say <5 things.