Tire Pressure Adjustment Clarification

I think I have a clear understanding of tire pressure as it relates to temperature readings.  My question concerns adjustments to pressure in response to loose/tight conditions.  The way I understand it, increasing/decreasing pressure has the same effect as a spring rate change for that particular corner.  For example, increasing RR pressure should make you looser, and increasing RF pressure would make you tighter.  My question, (assuming above is correct), since the diagonal of each corner produces the same results with same direction of change:  Why would a team decide to raise RR pressure versus raising LF pressure to loosen the car up.  What are the differences between these two adjustments. And even one step further, what is the difference in lowering the RF pressure as opposed to increasing RR pressure for this same condition.  Just looking for some clarification on the subtle nuances between these changes.  Of course if my fundamentals are off to begin with, any enlightenment would be appreciated.