I was pondering how to make fills smoother, and it dawned on me that SOME of the parts in a Variation don't REALLY need to change, sometimes, during a fill, while others do.

Now, you can write these into the Fills by replacing the Part, but then you don't have as much variation when you DO want it. What's a boy to do?

Then it occurred to me... How about a Part Fill Lock button, so that pre-designated Parts keep playing the Variation, while those not 'tagged' go to the Fill? A front panel button or pedal choice to engage this, and now you have doubled the 'variation' in your fills!

What do you think?