WWCD probably refers to smashing and pillaging then building up an appetite from that and eating meat, drinking wine, and wenching in that order. Not exactly what Hulk would do, and it seems Conan often would strategize to win battles though this would often mean resisting his barbaric instincts. I think Grey Hulk was a bit like this but was generally thought of as not as strong or savage as the Hulk in it's purity. It could also mean planning out to smash and pillage however Howard did note that Conan never took a wench unwillingly (or had to for that matter).
However, not very moral by our standards but his god seemed to think highly of him. A bit like WWThorDo some might say. It could be WhatWouldaTexanDo considering Howard was from Texas.
One of the nice things about the stories is that they range from short to novels. Always fun, even the ones that were completed by his archivists later on past his demise.
One of my friends, a corpsman said he had a great way to get back at the Chief whenever they would reach shore. Hilarious but he got busted big time for it. Still, he said it was worth it.