Yeah, I mean if you wanna refute factual math and say it's not a "solid reflection of reality", by all means, go on living whatever "reality" you wish.
For the rest of us, it's nice knowing what the changes brought. As the proof showed, TBN can most certainly be converted into terms of DPS. If you're interpreting it as "raid-wide" DPS, then just stop, because I made no comment whatsoever on that matter, and most people already know that there are benefits that will outweigh the penalty.
In no way, shape, or form did I say TBN is useless on another tank, nor did I say it's not worth using. Nor did I say that DPS was in any way the primary function of this ability. It will always be a personal DPS loss while not in Grit, whether you choose to believe it or not.
That being said, being in Grit will change the matter considering that the potency is different, and it's most likely going to exceed the additional opportunity cost of Syphon Strike's 2400MP.