Does anybody tried to use it on regular basis? I tried today and it's like worst gap closer I ever saw. Your target will simply LOS or streak again after your first dagger, so when you are again in range to use it, 5 seconds already passed and you again don't have 2 GCD to use it... so far you need to sprint much closer then 22meters and only in that case you can gap close...
Imo ability should be changed in terms of range.. so for example first dagger have 28 meters range and 10 seconds duration to proc, but you can reactivate it for gap close only if you are within 22 meters.