When soldering people neglect the most important part of the job, keeping the tip clean. Soldering iron tips have a nickle coating on the tip that allows it to withstand many hours of proper soldering. The reason Weller's site says to use a light abrasive to remove scaling from a bad tip is because you really don't want to hurt that coating.

After each joint, wipe the tip off on a moist sponge to get the garbage off the tip. This will keep that crap from becoming that crud that needs to be scraped off. Before I put my iron away for the night, I coat it as it's cooling down with fresh solder, just before it's cool to the point where it won't melt the solder anymore. I let it cool with that on the tip and put it away. When the station is restarted again, that solder and rosin heat up and it is enough to clean the tip and condition it for the day.

My Hakko 936/908 are over a year old and the tip looks new. When my station is sitting idle, I turn the temp down to around 200. The iron will ramp up fast from there. I find no need to keep an iron that hot for nothing.