Drawing attention to the generally poor ability among engineers to use GD&T effectively (if at all) is always timely. Tolerancing errors sometimes become glaring visible even to management, yet the root cause of prototype or production problems is rarely addressed. What is also a huge cost goes unnoticed. Unnecessarily tight tolerances added substantial cost to nearly every design I reviewed; I generally found the offending engineer unable to understand the analysis and unwilling to risk loosening the belt and suspenders.
Interestingly, it was during the transition from 2D to 3D, but prior to effective CAM tool availability, that I noted a dramatic increase in the GD&T knowledge of quality engineers. This was often enforced by the necessity of programming CMMs. In fact, I frequently worked with mere inspectors who had a better working knowledge of GD&T than the resident Mech and Manufacturing Engineers.
Since few engineers now work in an environment that houses manufacturing, and more design is done in 3D, GD&T knowledge is more critical than ever before. The design might well be manufactured half a world away by a team that would have difficulty providing feedback even if they spoke the same language. Facility among engineers with GD&T is part of an effective DFM strategy. To have quality or manufacturing engineers, or "checkers" clean up a design after the fact is not as efficient as having the design engineer get it right. And knowledge coupled with use of tools that evaluate stack-up is imperative. Ignoring this guarantees that even advanced mechanical engineering will follow manufacturing offshore.
Operations Mgmt (emeritus)
(errr...good deed doer)