ObamaCare and the 'RobertsTax'

The American Thinker reports:

If having provisions for enforcement is necessary for a "tax" to really be a tax, then the RobertsTax isn't a tax at all -- it's a suggestion. That's because ObamaCare expressly forbids the IRS from prosecution for nonpayment of the RobertsTax. However, the IRS can deny the taxpayer his income tax refund if he owes the RobertsTax. (This has been addressed at The American, Forbes, Reason, NPR, Businessweek and elsewhere.) But if denial of one's income tax refund is the only mechanism available to the IRS to enforce the RobertsTax, then the RobertsTax can be easily avoided by simply not overpaying one's income tax throughout the tax year.