[SRW]

Do they work? My right shoulder is starting to object, I am not really looking for any of the automated gizmos, just something that will go a bit further then my pathetic efforts...
do you use one ?

Yes they work but I am not sure that it will be any easier on your shoulder.
Bumpers with a rope are much easier to throw than a ball. Much less effort needed with the rope and weight.

Also, I assume you have a left arm?
Toss bumpers every day left handed and you will quickly get used to it.

 

[SRW]

grandkids coming for a visit in the summer,

grandkids throwers coming for a visit in the summer

 

[SRW]

use both hands over your head

Forgive me for laughing.