About 15 yrs ago I had a person beg for 2 boys, assuring me that one would work and travel with him, the other stay with his wife. This was not an inexperienced person–in fact he had a wildlife license to keep and rehab large cats. I agreed but called my stud owner who utterly, totally flipped out on me. His points were valid-- that having the same sex set things up iffy (these were Rottweilers btw, not basenjis) to begin with, and that even choosing temperaments, I still risked one being dominated and fights and WHY would I do that when I had many homes waiting? The people, btw, were not too happy but agreed on one boy and about 6 mos later asked me to help them find a breeder for a bitch (spay/neuter contract).
That said, I know many who have kept 2 from a litter and had no issues, but again, not inexperienced folks. I don't think a breeder is evil or horrible to allow 2 in one home, but knowing that one at a time with some spacing is better for the dog, I probably would wonder about a breeder doing that. Like Pat said to me, why would you compromise chances for great homing and bonding? And if I were a breeder, I'd wonder about an owner so anxious to get their immediate needs met that they would rather get two than wait a bit. It would have to be very valid reasons imho or I'd probably not want that person to have ANY of my pups.
So then I have to admit that we have quite a few of the Wimauma rescues who took 2 at once. NO ONE (we have our own FB group) is having issues because they have done the things needed and because placements were carefully selected and screened. These pups are now all over 2 yrs old. So I am not saying it can't be done and never would, but it would have to be some awesome reason why and they would, like you, have to have truly worked out what the plan was.