Portrait of a Devout Mormon
Since it is common knowledge that Mormons-in-good-standing are punctilious about their 10% tithe, here is a plausible scenario for Romney's refusal to release tax records. http://abcnews.go.com/blogs/politics/2012/08/romney-says-itstithing-that-keeps-him-from-releasing-tax-returns/
It is unlikely that Romney would donate more than 10% to LDS.
It is more likely that Romney refuses to release his tax records because fellow Mormons would then realize that he is paying far less than his "due."
It is not inconceivable that Romney's wife is also unaware Mitt has been shortchanging the church.
Big trouble at church. And big trouble with the wife.
"If Momma ain't happy, ain't no one happy."