Well I didn´t vote in this challenge but I would probably have given this a 5 or maybe a 4 depending on how I thought it stacked up in the challenge. I kindof think you met the challenge, I mean the model is I guess supposed to look like a caveman wich is what most people think of right away when you say missing link. However, that outfit is hardly convincing as a caveman, if you could have gotten your hands on some fur (fake or real) the costume would have been much more convincing and led you to a better score. I am not a golfer, have absolutely no insight or interest in the sport and first thing I thought when I saw the shot is what is that in his hand. I just saw a cane and not a golf club and I thought the golf bag was some sort of cape. It wasn´t till I read the other comments you got that I saw it was a golf club and a golf bag. The title didn´t help me either as I have no clue on who the Encino Man is or what "Missing The Links" stands for, I had to google that frase to know that links stands for golfing. That´s probably cause english is only my third language and I have never had the use for that word yet so at least I learned something from this picture :)
What I am trying to say is if I were voting, I would just have seen a guy with a cane in a goofy outfit and a cape and while I assume most native english people got it, maybe some like me who aren´t didn´t get it and voted lower.
Regarding the composition, I think that is the weakest part of the photograph. I do normally like slanted photos but in this one, the fence is just too prominent, it´s very much just eating up space and draws way way too much attention, it´s the first thing I see when looking at this photo. I would suggest you trying out other angles, go down lower or higher, take this in landscape instead of portrait orientation or whatever, maybe include that fence but not have it such a big part of the photo as the guy I assume was intended as the main subject.
Colors are not bad but a bit too cold WB wise for my taste, looks like you used the daylight setting when perhaps the shade or cloud setting would have left you with warmer and more pleasant tones. Regardless of what you used and what the conditions were, I still would have prefered a warmer WB than the one was used.
Also the shot is just a tad too flat contrast wise for my personal taste and could stand to be sharper, but that´s just me :)
Funny shot. Looks like ya picked a bad time of day to try and shoot this though as the lighting is a little lacking. Some fill flash would probably have helped with the shadows on his face.
TC
The golf joke seemed less clever every time it came up, but I like how you've combined golf with the other meaning in such a ludicrous fashion. Also, it looks like he's wearing velvet. Any caveman in velvet and glasses deserves at least an 8.
I'm trying to think of another really bad pun as a comeback, but I'm sorry, I've got nothing. As for the image, incorrect white balance is my pet hate. In overcast conditions, many cameras require manual switching to cloudy or shade setting to get proper colour reproduction.