There is a bug right now regarding abiltiies with high speeds like Quick Boomerang and Oil Slider. When used by the player they always go first (as they should), but when used by the target they seem to ignore the ability speed. This is because the target's action (switch, ability, etc.) is calculated much before the details of that action (like which ability is used) and the speed does not have a chance to take effect. I am working on a fix, but it will require rewriting some code and may take a little while. Please be patient in the mean time and enjoy your advantage over your opponent. :P