The key is breaking up the blob, which is what deer distinguish or are alerted to - like said breaking up the outline. There is little doubt once a deer is locked on your position he/she sees something that just isn't right and that is when if you can sit motionless and remain undetected to the more prodominant scent a whitetail or other game rely on you may just get lucky. This is were breaking up your outline by either camo or using natural cover is worth while. I choose to use predator brand camo for a couple of reasons;
a) break up technology vs blend(something I have long believed in)
b) patterns are best suited for my enviroment
c) ground hunt mostly
d) predator garments have serviced me well, IMO they are an excellent product for the wear n' tear/washing I put on my outerwear.

I can only wear camo for Bow and ML season here, during rifle we must wear solid colours of blaze,white, red or yellow(no camo blaze either-SOLID). If I believed camo was the main reason for being successful I would be hooped come rifle season. However it has simply further endorsed my opinion on what works to throw off a deer eyes is in fact outline break up. When I dawn my solid suit I hunt the same way as if I had on my predator camo, I look for areas when setting up that offer natural breakup to my outline. Which includes front, side and more importantly rear ward. Sitting on a crest of a hill might give you a good vantage point but it also places you in direct contrast with the skyline behind you---regardless of the camo or clothing you wear - thus will draw the attention of game for miles. To be successful you need to place your self in a position to be successful in the first place, the example I just gave wouldn't be one of those situations to reward success on a regular basis.

Not all camo is created or works equal but a lot is based on your area, some patterns would offer little to your concealment or outline break up, while others will work in a variety...best advice when buying camo is a pick a pattern that encompasses your areas backdrop and seasons..not the prettiest or latest thing.

I agree jagman with your underlying theme though, a lot is placed on the technology side vs the smarts side for hunters today...latest in greatest doesn't work unless you have the basics and for those of us who have changed our gear most likely have changed our knowledge base as well which is more a direct reflection of how we fare in the field. Unfortunately we are a marketing crew and believe those who say you can't live without this product. While mant things have enabled us to be more accurate or effective in some way the true reason lie within. It boils down to confidence, knowledge, experience, etc. I have long said if you feel more confident with an item then it will transpire to the field and if you want to thank that item or items than go right ahead but you are the real reason it turned out that way! For some it is essential to have that brain up factor and others the old suit, bow and 7x35's nocs work just dandy thank you very much.

Long in short a puzzle don't make a picture until all the pieces are in place, camo is just one small piece of the puzzle and certainly not the centre piece either!