You're right about ABA not being rocket science. I don't understand why you are being so defensive about it.
You are clearly a committed parent who has found a way of reaching her children and that is great.
It is important though that the OP and any other readers get factual information about ABA programmes and to suggest that it turns children into robots is daft and need to be corrected.
To suggest it breaks up marriages is also untrue. To suggest it is stressful, well, it can be in some situations I grant you, but some of that stress is brought about BECAUSE it isn't understood by other people.
The efficacy of ABA IS proven, but with all research with each publication of a study come questions and further avenues to explore, in the same way that breastfeeding isn't proven to be good for babies. The evidence is there due to the multitude of studies, but if someone had an agenda to, they would find something about it that isn't yet proven, or at least isn't conclusive. This doesn't however, mean that it is bad for the child.
I don't know when your husband last reviewed the literature and studies on ABA, but there has been a flury of activity over the last 5 years, plus ABA itself has developed quite considerably, mainly to account for the developmental aspects rather than simply based on demonstrated skills, as well as focussing more on language and social interaction.
By correcting your lack of knowledge wrt ABA I am in no way challenging the approach or combination of approaches that you have used with your children by the way.