[maestro pistolero]

It's hard to tell whether your wrists are locked or not in that video. I do notice that when the gun recoils, the muzzle is lingering in it's partially recoiled position rather than dropping right back down on target like it should.

In establishing a repeatable grip, it is very difficult, at first, to distinguish the difference between white knuckling your pistol grip with your fingers, and actually locking your wrists. The two different types of pressure feel the same in the hand until you teach yourself to distinguish them.

To begin to get familiar with the difference it is useful to isolate the two types of muscle tension:

First, grip your gun with lots of finger tension from both hands, but purposely unlock your wrists so that the gun can be moved vertically very easily.

Then use moderate to light finger tension but lock your wrist completely. Notice the difference between how that feels and learn to differentiate the two types of pressure.

By doing this you can learn to more purposefully regulate the amount of tension devoted to wrist-lock verses gripping the gun.

Elbows should be somewhat firm but definitely not locked. If you lock your elbows, you are now transferring all the recoil to your body rather than your arms where you can create a sort of shock absorber that allows for fast follow-up shots.

One last point, many competitive shooters now position their off-hand with the wrist in its downward broken position, so that the off hand thumb is pointing directly at the target in line with the muzzle (and parallel to the pistol frame).

This is a sort of wrist lock for the offhand that gets overlooked a lot when developing a grip.

There are plenty of videos on YouTube showing all aspects of this modern, competitive/tactical grip that is widely used now. I think you will improve quickly by studying these a bit.

Hope this helps.