Couldn't agree more.
Jennifer is totally correct in that your wife has no vested interest in the person at work, but it is one hell of a chance we take in telling. Consider carefully, especially to the point of whether you can accept the worst possible outcome. Sorry to be a harbinger of doom, but as a pessimist, I am only ever pleasantly surprised.
I used Jennifer's letter as a template for my big reveal. If you do go for broke at some point, sincere best wishes from me to you for a happy outcome.
Rebecca