Yes, I know the manufacturer recommends disassembly and repack every year.  I think based on the amount of miles that I have driven that annual repack is over kill. What say ye?

I think its more likely with electric trailer brakes that they aren't working properly and are not getting hot, or are working well on one side and not the other. Pulling the drums provides the opportunity to check that. If there is little or uneven brake shoe or drum wear, the magnet wear surfaces are scored, or the actuator arms, pivots, and springs are frozen or corroded then its time to look more closely and see what's up. The crappy insulation displacement connectors are one likely suspect, that would be a good time to change them out for butt connectors and self sealing heat shrink tubing. 

Personally, I don't bother taking the time to clean bearings, just wipe them with a clean rag, inspect, and press fresh grease through them till you see the new grease oozing out, put them back in the drum, install a new seal and done.  Doesn't take near as long or make as much mess that way. I don't really see what completely cleaning them does for you other than maybe leaving some solvent in the bearings. 

Ours has crimped connectors all around underneath. Maybe the displacement connectors is an eastern thing?

It took a bit to figure out why my brakes were grabbing to one side only to find out that the wire got pulled out, and then sprung back to be "close" to the same location.

A wee bit frustrating to see how they just left it hanging there unprotected and unsecured.

Could be, or maybe FR at some point decided to switch to using real connectors? 

That's a possibility. Ours is a 2017 (late 2016 manufacture), so we have at least a year newer version.

If your engine or trans quits or a bearing overheats you might get stuck on the side of the road. If your brakes or tires fail you can die, so for me brakes and tires come first. I've experienced a couple of brake failures and a really bad brake imbalance before so I guess I'm probably a bit paranoid about it. 

 Once you get your brakes set up and working as they should and your brake controller is set up the way you want it, here's a nice easy procedure you can do when you head out on a trip to verify things. 

If you do this first with known good brakes and have a baseline and things haven't changed then you can probably get by with just EZ lube for awhile. You can also use the ir thermometer on the hubs and tires to see if your bearings or tires are getting hot. And you can use it for your TV brakes and tires too.  I keep mine in my center console and do this at every gas stop, doesn't take but a few seconds.