Aint nothin but a Gb thing baby

[MartyNeilan]

You could try it as a "false tone". 2-3 might work best, but you could also try 1-2 and 3 only and see what sounds most in tune. False tones vary widely depending on the horn. I have been fooling around with them on my 4 rotor CC. The slots are -super- wide and the tone may be different - right now my concern is trying to keep them from sounding too woofy compared to nearby valved notes.
My buddy Bob should be have something to say on this soon - he is the false tone man.
I have never viewed them as much more than a novelty until I had my 6/4 3 valve Martin, where they actually worked quite well. Some bass trombonists even use false tones to compensate for lack of a double rotor. Some guy named George out in LA has been doing that for a little while, and it has worked out pretty good for him when he doesn't have time for an E pull.