Very interesting Ian; that's quite a fine nozzle indeed. How large of a bore are you referring to when you mention the crunchies??

You bring up a good point about delivery; a high pressure nozzle would make a long addition easier and more consistent, compared to low pressure where the accuracy of delivery is all controlled by your muscles. With high pressure you kinda just 'give it hell' and it ejects as fast as it can. We've been using Mark O's bulb thingy which works on that principle; you squeeze it 100% and the rate is more or less controlled by the constant pressure you've created in the system.

And then there's this option (warning: eye candy)...