Double Bash w/ Very Slow

Is it really not possible? I saw someone doing it with a Demonic Death Penalty Blade, which is a Very Slow weapon.

Allow me to be perplexed. I changed this a while ago after someone proved me wrong. Its just that the time window is at the end of the zone, and becomes exceedingly difficult to do for very slow weapons. Its not impossible, but it might as well be for folks who's lag isn't optimal, or in the case that more lag actually can allow the window to expand, too optimal.