Quote - It seems the magnetize pose fixes one thing and makes it worse elsewhere.

That is a fact.  Fun, isn't it?  Also, using something like Morphing Clothes to make morphs to match V4's JCM usually isn't enough, or makes matters worse, depending.

You can't fix it with Joint Parameters -- you are likely to just break other poses and pull your hair out in the process.

BTW, you can expect the same thing with a sleeved item.  Shoulders can be equally fun.  This is one of the reasons why the Marketplace is full of sleeveless tops and mini skirts that are so short they barely cover Vicky's hoo hah.  V4's thigh and shoulder joints are the devil incarnate for clothes makers.

You need to create your own custom JCM for the pants.  View the mesh in Poser or DS with the leg bent to -100 or -90 and count polygons from a point of reference (that pocket or the waistband), so you can locate the problem area on the unbent clothes in your modeler.  Make a morph that pulls that area out quite a bit, and up a little.  Be sure to include some of the inner thigh toward the crotch as well.  It will be buried there farther than you can see.  Put the resulting morph deltas into a channel that looks something like this:

        targetGeom JThighBendFwdR
            {
            name JThighBendFwdR
            initValue 0
            hidden 1
            forceLimits 1
            min 0
            max 1.1
            trackingScale 0.02
            keys
                {
                static  0
                k  0  0
                }
            interpStyleLocked 0
            valueOpDeltaAdd
            Figure
            rThigh
            xrot
            deltaAddDelta -0.011111
            indexes (number varies with model)
            numbDeltas (number varies with model)
            deltas
            (...... delta info here)
  

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