Bill Tindall, E.Tn.
I don't test but I do look with a 10X lens which I keep at hand for all sorts of observations. It reveals that pesky wire edge you speak of. Actually it reveals a lot about the state of the edge before and after sharpening.

The lens gets employed when trying to figure out what direction was used that resulted in tear-out when the defect is too small to reliably judge by feel or naked eye examination. Also use it for repairs to see that they are good and for examining stringing intersections...etc. Indispensable.