I'm with you Creamie. We spend hours studying compasses when we do our theory,whether it be for a pilot licence or a yacht master ticket. On my boat I often compare GPS against compass when in calm water so that there is little drift to worry about. Or if I am really keen I run a transit check, which to the uninitiated is similar to being on a taxiway or runway aligned with a known bearing..That way I know that ithe compass is within 5 to 8 degrees on all points. That is good enough because I can't steer better than that anyway.
The regulations require pilots to do an instrument check every flight. Surely that includes a basic confidence check of the wet compass. We learned all about it to pass those exams, right?
At the point where it is too far out of whack to be good enough to get you home in an emergency - say 15 degrees - may be the time to call in the adjuster. Or DIY and don't say anything.....(just kidding, but again we did learn how to do it in theory).
But if it ain't broke, don't fix it.
To those who advocate blind obedience to CASA, try flying a typical golf ball wet compass to better than plus or minus 15 degrees in turbulence and let me know how you get on.