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Dynamic Analysis Question / Visual Analysis

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IES didn't answer this question for me, so I am bringing it here.

A question some Visual Analysis Users may have come across for themselves, and
perhaps solved, and perhaps others using dynamic analyses in building design.

It is about the properties that can be attributed to a node.  In Visual Analysis it allows
a rotational mass to be attributed, with lb-ft-s^2 / deg as units.

What would this mean?  It has been along time since dynamics course in BS. studies.
Anyone able to apply this in dynamic analysis?  How would it have an effect?
Do we not also have to account for 5% accidental torsion in dynamics?  I assume
this could be useful here if necessary.

If so, I am trying to visualize how it works.  If you apply a mass with rotational
properties to a frame point, such that the frame would try to rotate at that point,
then for modal analysis, masses at differentlevels would either rotate in the same
direction or in opposite directions.  I suppose then the first rotational mode
would include all of them rotating together.

If there is any feedback, would appreciate it.

Regards,
Refugio Rochin