There was a thread recently that some considered out of hand, I guess.  I think (not sure) it started because a guy admitted that at some point he somehow had a dick in his mouth.  I saw a comment about it and tossed in a guyfact that you can't unsuck a dick.  Many others joined in and a few guys got deservedly hogpiled because they took it seriously and/or chose to justify it.  A frequent flyer flew in on her broomstick to straighten our asses out about the terminology being used with a solid full paragraph of gendersplaining.  Then poof, it had been gutted.  

More Guyfacts;  (should be taught as young as 3)

-If you're going to shake hands with someone, stand up.
-Shake with a firm grip and look them in the eye
-If you think you may need it in the future, keep it.  If this gets out of control, build a shed.
-you can damn near have a  complete conversation with another man you've never met with a simple head nod.  
-You can correct one time while backing up a trailer only if it's new.  Anything more, you lose a man card.
-if your dick has been inside another dude, your gay or bi forever...ie..you can't unsuck a dick.

Stuff like that..feel free to add more!