Ribs Stuck in Vermont

Angela Smith of Classic Form Pilates in Burlington, Vermont writes:

Help Me Sister!

I have a new client who has presented me with a puzzler.  It's a man, in his 40s, athletic all his life, in good shape, no flexibility at all.  The issue is his ribs - he can't drop them.  There's no movement at all.  I've tried every trick and visualization I know to help him out but it's not working.  He has a fairly broad chest and his ribs are just stuck.  Any thoughts on how to help him (and others who are like him) to learn to funnel those ribs?