Guilin Sun
Ansys Employee

“Is the index monitor then only showing the diagonal form of the matrix -- such that it is actually consistent with my expectation plots? ”

You are absolutely right, currently.

Currently it can only show the diagonal elements which is the input data, without transformaiton matrix effect. Things can change later.

Please check the feature website: https://forum.ansys.com/forums/topic/vote-new-features-and-file-your-feature-request/ you may file this feature again if it has not published for vote.