You know this brings up a really good point to make. I once spoke with a breeder that wouldn't let any of her pets go to their new homes without being fixed first. That meant if you were going to get your new puppy during a good bonding time, 8 weeks, either you got a spayed/neutered dog at a very young age or you had to wait until they were old enough to be spayed/neutered which meant you missed out on the good age to bond with puppy. Some will disagree with me about ages to bond with puppies but there has been research done on when a good time to rehome puppies is and 8-10 weeks seems to be the mark.Considering everything I read so far and being a biologist, I know that I personally would wait till 8 mos to a year at least - possibly longer.
Removing ANY gland in the body has tremendous effect on the development of any animal and downplaying that fact is silly, in my humble opinion.
Just because we do not see effects with the naked eye, does not mean that they are not happening.
Anybody who went through a puberty, pregnancy or menopause should "reflect" and would get just a glimpse of how much sex-hormones effect the body AND the brain.
I had Harry neutered when he was about 14 months or so and he never made it to hike the leg status and he still humped the rescue I got that was in heat. I don't think humping has as much to do with sexual energy as it does pack status. That's often a misconception people have about dogs humping each other because neutered dogs and even females hump other dogs to show dominance to that dog.