Great! It makes me wonder why anybody uses 9-ball retainers.

But I like that idea of loose bearings. I only used retainers because that's what this bike had when I got it. All my bikes have been second-hand, and until this one they came to me with 11 loose bearings in each cup. I just copied what I found, and didn't realize it was an option. I had less trouble with those old bikes and their 11 loose bearings, even though I was making the same mistake back then when adjusting the bottom bracket. I've got a new spindle on order. When it comes, maybe I'll install it with all new ball bearings without retainers, just like old times.

Or maybe I should switch to a cartridge, assuming that's possible. Is that another option? A square-taper JIS cartridge? That would work, wouldn't it? I think I just need to buy some crank bolts and a splined wrench. Any opinions on whether it's a good idea to switch over? I gather that cartridges are much more widely used now, judging by the availability of parts. Do they last longer? It sounds like they don't take any adjustment, which I don't get around to as often as I should anyway, and which this forum thread shows I haven't been doing a very good job of. And it probably wouldn't be much more expensive, given that I keep having to buy new spindles and cups when I finally do get around to servicing the BB.