for whatever reason he LOVES my husband! Crawls all over him, and well.... trys to "hump" him.
He does indeed love your husband and wants to play with him.
He has done this to Max several times now... I think it is completely ineffective
You are right. If it was effective, the dog wouldn't do it anymore and your husband wouldn't have to keep doing it.
If it were my dog, I would keep him away from your husband. If you can't make your husband quit what he's doing, then I wouldn't give him the opportunity.
Ideally, when the dog started humping, your husband would say "uh-uh" and stand up and turn his back, in essence, saying, "I won't play with you if you do that". Eventually, the dog will learn that humping the man of his dreams takes his attention away.
That's the only way I know to stop the behavior.
Failing that, YOU (or your son) can try watching and redirecting the dog. In other words, when the dog starts humping, stand up, say "uh-uh" and call him away and do something enjoyable. Take him into another room. Give his a stuffed kong or something else to occupy him.
Or you can put a few coins in a pop can and tape the top shut. When the dog goes for hubby's leg, toss the can on the ground so it makes an unpleasant sound and gets the dog's attention. Then praise and redirect him to something else.
You can also leash him, crate him or otherwise keep him from performing his love dance. All of the suggestions except for the first, where your husband is involved, are just managing the situation. I'd much prefer that your husband handle it correctly, but I don't know if he's willing.