Hello Anaxial,
Thank you for your message regarding the paragraph I appended to the Samson article.
No citation is possible, as I tried to make it clear that this explanation is speculative. I learned it many years ago, from a minister who I believe got this interpretation during Seminary training. While it cannot be proven (and indeed the entire Samson story cannot be proven), it gives a more plausible explanation of Deliliah's act of treachery than claiming that she cut his hair, and thus rendered him substantially powerless. And it explains why Samson's captors would have treated him in the same manner as oxen were treated in those times, as a form of enduring humiliation to their enemy.
As is well known (and is outlined in the Wiki article on castration), the act dramatically reduces aggressiveness in males of all species. Samson was powerful enough to break bonds of new rope, and could likely have broken free from his millwheel, but for being deprived (i.e., shorn) of his previous extreme aggressiveness.
Hence I think this interpretation merits inclusion, so long as it is made clear that it is only a plausible speculation. You might wish to restore it, with perhaps expanded wording stating that it is no more than a possible interpretation, but one that adds reasonableness to a tale that otherwise requires accepting that an angel (or God himself) made a direct intervention and caused a significant (but not lasting) change in one human being -- a Draconian punishment for having his hair involuntarily cut.
Kent