MargaretToigo wrote:Now, I could probably get better results fitting the dress on the tights and skirt helpers, rather than the human, but in my experience, the armpit distortion during posing thing happens slightly less when the human is used, but then the fit in rest pose is more universal when helpers are used.
It is definitely not the same distortion. (Take a closer look). There is a sudden gradation to humerus (upper arm) from deltoid (shoulder) that doesn't happen in my model's garment.
You will need to follow the edge loops around the armpit until you find the one vertex that has been mis-assigned. I use the Object Properties panel, opened with the 'n' key. You can then control the influence on this vertex by changing Vertex Weights.
At this point, I would have to say the problem is in the MakeClothes code; it would have to be rewritten for my 'shoulder-harness' approach. That's one of the reasons I've stayed away from using MC for the time being.
Notice how the 'ring's around the shoulder deform very differently from the problem you had with shoulder deformations in your suit.
The difference between your garment and mine is the weight painting. I used the automatic weight painting available in the Parent to Armature (Ctrl - p) command set. It is a bit of overkill, but works in simple garments.