I haven't had any real issues with corrosion but blueing it does sound interesting.
bertsmobile1 - Regarding maintenance - I've tried the following and never really made it through a season without it degrading significantly and early:
1) Cleaned adjusters and bushings, used bearing grease as lube - Worked OK for ~5 - 10 hours
2) Replaced adjusters and bushings, replaced belt, bearing grease as lube - Worked OK for ~5 - 10 hours
3) Replaced adjusters and bushings with "new" design since my old replacements were defective according to Honda - bearing grease as lube - Worked OK for ~5 - 10 hours
4) Cleaned adjusters and bushings - tried graphite dry lube - Worked OK for half a season, but would still want to drag, helped to tilt the mower to redistribute the graphite occasionally. Not kidding.
5) Replaced the adjusters and bushings - teflon dry lube spray - Worked great for ~1 hour, worked OK for ~1 hour, then worked horrible and locked up SOLID. I do NOT recommend this method.
6) Installed grease fittings on the adjusters - Worked awesome for a while, but required constant greasing as the grease would get dirty. Basically I was greasing it almost every mow and the bushings were getting PACKED with gunk. Eventually it just pushed the seals out and failed to do much of anything. It basically got me through an entire season of decent mowing though.
7) This experiment here - Added extra dust seals for the wheel side, converted from plastic bushings to needle bearings. So far this is working by far the best of anything I've tried. If it makes it a full season without me having to think about it, it'll be a massive success in my opinion.
My yard is less than 1/2 an acre. It's STUPID hilly, and pretty dusty at times. I mow twice a week for about 45 minutes. I believe annual maintenance and cleaning of this system should be considered "reasonable" however I've not found a setup yet (besides POTENTIALLY the bearings) that allow me to run it all season without getting significant drag when pulling it backwards. I believe most people have this problem, but simply aren't tuned into it until it gets really bad or they somehow realize it. The design is flawed, not my maintenance of my mower.