Chuck
Yes that’s series resistance just for info:
It depends on what you’re trying to do the way you’ve got it wired as you know would give you a variable resistor in place of R2 your series resistance would be added in both directions and no jumper would be required
In this case between lugs 1 and 2 and 1 and 3 both CW and CCW it wouldn’t add anything between lugs 2 and 3 in either direction
So if you were using it so that when turned down it wouldn’t completely turn off, on a gain pot for example that should work
If you added resistance to lug 2 turned either way it would add resistance between lugs 1 and 2 and 2 and 3 but not 1 and 3 basically it’ll only affect whatever lug connects to the lug with added resistance
The best thing to do is get your meter out solder resistors on, use a clip as a jumper and experiment
That’s what I do because I can never remember what happens