Sarah Palin wore the short, cropped jacket styles, but hers were made well and fitted well. Compare the fit on the sleeves. Michelle's jacket is cheaply made, without the needed interlinings in the collar, lapels and hem, and inadequately pressed -- although the construction of Michelle's garment and the woolen fabric is of such low quality it wouldn't even press well.
I sew and I agree with every word you said.
As a long-time seamstress, that's exactly what I was seeing. The sleeves give it away, as does the fact that viewing it from the front, the jacket looks too small to be buttoned up. She's a large woman (as am I) and for our types, it's even more important to have clothes that fit well. Well fitting clothes never make you look bigger, but trying to pour a large size into something too small just accentuates the size.