I have a question about the amount of stabilization to expect from a gimbal or unlocked ball head.

In the past I have mostly shot hand-held. Occasionally I have used a tripod with the ball head completely locked down and with remote shutter release.

I am now interested in using a tripod with hands on camera to track slowly moving subjects. The most recent example was a duck swimming by. I’m not thinking birds-in-flight at this point!

I recently experimented with this indoors at a distance of about 20 meters. Handholding a 400mm non-IS lens on a full frame camera my slowest shutter speed was 1/400 second. That produced sharp shots more than one-half the time. With my light “travel” tripod and ball head I could slow the shutter speed to about 1/100, or about 2 stops stabilization for equivalent results. With my heavy tripod and ball head I could go to 1/50 and still get about one-half of the shots sharp.

How much stabilization should I expect if I really got in practice with this technique?

I can understand that a gimbal makes it easier to track vertical movements. Does a gimbal vs ball head matter with regard to degree of stabilization?

Thanks for any insights.