Indeed, I saw him packing the bearings, he did it and he did it right. Too much time and too many miles. No silver bullets or pixie dust for these small axles. Closest thing to it is prolly the EZLube, where if old grease pushed out by the new grease is water-contaminated, you know you need to inspect the bearings for damage and then repack (or replace).
Dexter now says 12Kmiles or 12 months, but that's pushing it, based on my experiences with a number of trailers and the experiences of others, esp if the trailer sits a lot so the grease sets up and corrosion forms on the axle
at the seals.
Look at it this way -- Most trailer folks carry extra bearing/seal sets and have had occasion to use them; it's darn rare to find anyone carrying bearings for their truck/car -- There's a reason behind those practices.
The real problem in my case (after owner stupidity) was water intrusion thru the seal over time. You just can't expect the life of these bearings to equal the beefy bearings and even beefier seals on trucks and cars. I am now a religious checker of tire and hub temps all the way around whenever I stop; even bought an infra-red temp checker at Radio Shack.
BTW, if your bearings are so tight that you can't get a tiny amount of play when pulling the tire, they are too tight...
Pete and Rats