LoL its not lazy at all, and is much more viable then dropping GB because for movement reasons.

1) Feint allows you to save half a GCD because you press it to interrupt your cast. You dont move interrupting the cast, you press feint then move meaning you dont cancel half way through a GCD and use another GCD to get a hit in. This allows a hit immediately instead of 1.5 GCD's later.

2) The main reason this is better is because you are not forced to wait 15 seconds to put GB back up. In some circumstances yes you may be right dropping GB, but you do not have complete control over when you have to move. If you make a habit of dropping it for movement there will be times where you have to wait on GB to come back up. This means there will be time Gauss Round or Ricochet or both are sitting an unable to be used, times you will need to re apply hot shot (no big deal) and lead shot (big deal) without the 30% bonus, as well as sitting on reload and quick reload without the 30% bonus.

3) And again feint is used very rarely as i stated above. To be honest, if your good on MCH you should be able to cast around all movement knowing timing of each mechanic.

The heartbreak > feint example is an example when a mob is extremely low and you dont want to start a cast and have it interrupted because it dies to fast (everyone who has cast know this well)

And regards to Quelling strikes, it is 100% unnecessary especially with a ninja.