that makes sense. I picked up some more 5/32" bearings this afternoon & I'll try them. I had something similar in a very well-worn MTB I rejuvenated a few months ago...but it was generally notchy more than centered on any particular point. On that bike replaced that one with loose balls top & bottom (more to see if it would make a difference & give myself a real stark before/after comparison)...and, barring another rode-hard-put-up-wet 20 years that bike had between 1987-2009, I'd fetch a guess it's good for another 20 years as a tank of an urban assault bike...in other words, it's veeeeeerrrrrrryyyyy smooth. So, that's a long way of saying maybe I could expect the same result here?
Also...so, a split crown race may be a factory thing for this headset?
(OK, promise not to belabor it any longer...if the new bearings to smooth it up, I'll pick up a new headset + the tools I need to change it properly)