Swing arm maintenace

[Idaho]

With my rear wheel off of the bike and most of the stuff out of the way I'm contemplating a lube job for the swing are bearings. (not even sure why there are bearings here as opposed to a brass sleeve but that is not the point) Gadgets page gives great directions on how to lube the bearings and also how to modify the sleeve with grooves to facilitate the transfer of grease to the bearings. It started me to thinking about the groves along the axis of the sleeve relative to the needle bearings. Won't the bearings have a tendency to 'fall' into the grooves? Also it seems that it may be worth it to have to dis-assemble the swing arm for proper inspection and maintenance and may be a valid reason to not install a zerk. So I thought that I would refer this quandry to those far smarter than I for opinions. Hope this makes sense.
Thanks, Idaho