I think that makes sense. What set this whole thing off was chasing an off-idle stumble. Going from Orange to silver seemed to cure that. And while I'm at it, why don't I lean out the cruise just a little bit more... wait, what is wot doing???
An off-idle stumble won't be cured by the step up spring unless it's a WOT (or heavy throttle, at least) off-the-line stumble. A light throttle stumble is a lean idle circuit, which is outside the scope of what we're talking about here. If it were my car, I'd go back to the orange spring and get your jetting closer to the #23 and #26 we talked about above and see how it works. If you then have an off-idle stumble, we can talk about it then.