#####So if a dog breeder can't do something, it is impossible in principle? I never knew of an omnipotent dog breeder.#####
I never knew of an omnipotent random chance! :-)
Evolutionists seem to have reversed to logical order of things. Normally, if a barrier is encountered in science that can't be crossed, it's assumed to be a pretty rock solid barrier. Does that mean it can literally NEVER be crossed? Not necessarily. Perhaps there are ways to cross it that have yet to be discovered.
But until that occurs, you at least respect the barrier and don't arrogantly put forth a theory that requires breaching of that barrier in order for the theory to be viable. You might perhaps propose such a theory but you would concede that the inability thus far to break the barrier in question makes your theory problematic. It would seem rather presumptuous to put forth such a theory, then to cavalierly assert that we must all assume that the barrier we've never seen broken was frequently broken in the past but no one was around to see it.
In other words, you seem to be putting the burden of proof on the wrong people. If no one has been able to breed dogs, or anything else, beyond their natural species barrier, then the burden of proof falls on those who insist such barriers can not only be breached, but have been breached countless millions of times when no one was around to see it. The burden of proof isn't on those who claim these barriers can't be breached, it's on those who claim they can.
This is my problem with the arrogance with which the theory of evolution is put forth. Even though no one has ever observed life coming from its absence, we're told that it must have happened and we're to assume it happened unless we can prove it didn't. We're told that even though no one has breached the species barrier, that we're to assume it's happened millions of times because evolution requires it, and the burden is then placed on opponents to "prove" that it can never happen.
As I said before, I have no problem with evolution being offered as a theory, but given the scarcity of evidence for it and the list of seemingly impossible barriers to it, it should be offered up humbly rather than with certitude.
The "barrier" that you seem to hang your hat on is a completely arbitrary one. If a dog breeder tommorrow produces a dog that weighs 1 pound, you will move the goalposts and say that this is the new barrier. Up until now, no dog breeder has bred a dog smaller than a chihuahua, but there is no reason inherent in the genome of dogs that a smaller dog can't be produced. What mechanism exists to stop a 1 pound dog from being born? What evidence do you have for this mechanism (other than the observed size of dogs as that would give a circular argument). Another example: how many people in the eighteenth century were 7.5 feet tall? Remember, at 6 feet, George Washington was considered to be an exceptionally tall man. An eighteenth century person might well have stated that humans had a height barrier of say 6.5 feet. All you have to do is watch an NBA game to show that this statement is nonsense.