Dear Oldooz, I find this in my digital dictionary about "well":

verb [ intrans. ]
(of a liquid) rise to the surface and spill or be about to spill : tears were beginning to well in her eyes.
• (of an emotion) arise and become more intense : all the old bitterness began to well up inside her again.
ORIGIN Old English wella, of Germanic origin; related to Dutch wel and German Welle, ‘a wave.’

I have never seen this is-does combination, however. As an HL translator, I would have to ask the same question. It's wonderful that you do.

“Reality is as Reality does.” Wow! This would be a tough translation, Oldooz. I will try to help. I think this is a play of words on the phrase: “pretty is as pretty does.” I think this came from a novel somewhere, but of that I am not sure. I think the phrase could be described as a kind of “Americanism.” I always thought that it meant that a pretty girl’s behavior cast a sort of glow on how she looked, for better or worse. It meant to me that something like a smile makes a pretty face even prettier. In relation to this Heavenletter, I take it to mean that you cannot separate the idea of what Reality is from Reality itself. Or perhaps Reality cannot be described only experienced. Maybe someone else has better guidance on this? This is the best I can do.