This will increase your weapon damage output by 2.25x. This does NOT increase anything but weapon damage, so it does not increase flying kicks or tail rakes or DD procs (obviously). So if you are doing 400 dps with your h2h weapons or 2hb, this will increase to ~900 dps for the duration.
For max dps, it does not matter the weapon speed of your weapon, only ratio. A slower weapon does NOT benefit more from this than a fast weapon (test 18 speed vs 30+). So when you use this, just use your best weapon.