Thanks for your ideas Thom, Pete and John. I will try what John suggests. And see what a bit of virbrato sounds like in the mix, as Thom suggests (if I can walk and chew gum that is!).
One thing I have found, as John says, when using growl in the low notes - he describes it as garbled - is that the growl is very unstable. It sounds good for a second, then drops out and sounds rubbish, then with a little adjustment can get it back in, then it falls out again. John - do you try and hum lower than the note or higher, when down that low?
Pete - it is interesting what you said about Lee using a Harmonizer. Can you hear it in One Step Beyond, or is it more of a general observation. If you hear it in OSB, what interval do you think it is. My ears aren't trained enough to hear.
P.S. Pete and John - Your articles on SOTW about Rock 'n' Roll Sax are fantastic. I have printed them all out and have them by my bedside, which i read each night to try and internalise all that you've said. Excellent work.
Cheers,
Al