Sechel, I think it is you that is not understanding. You are predictably going to come in and say that “if you understood TT correctly, you would see that the Rebbe never put a Tanya on top of a Chumash.”
We know. The disconnect is that you seem to think that paturs him from the the rest of the issue. It doesn’t.
The only way you guys can dig yourselves out of this one is if you show that it was part of a bigger custom to never put any sefer on top of any other sefer and the fact that we’re discussing Tanya and Chumash is just coincidental choice. If that is the case, you could have easily said so, but it was not said (nor anything like it) in TT’s comment.