MORE THAN A FEW Maryland taxpayers must have perked up last month when Gov. Harry R. Hughes talked about his tax-relief plans -- a package that was labeled the "cornerstone" of the Hughes legislative agenda this year. At the time, the governor said his plan would cost the state nearly $34 million next year, which news accounts interpreted as the amount taxpayers would get back. But now comes word that the average savings will be about one-third of that amount, or maybe $11 for each eligible taxpayer in the next fiscal year. The $34-million figure, it turns out, included an amount that the state had been withholding and stashing away until annual tax refunds were sent out, and that it will no longer hold.Gov. Hughes was quick to emphasize that, while this may have been "misleading, it certainly wasn't intentional."

Maybe. But this revision illustrates the kind of careful math that politicians and taxpayers should take into account before making any or accepting any claims of fast, fast relief from the aches and burdens of taxes. In this particular instance, for example, the difference in estimates arises through the amount of money the state withholds from paychecks. Many taxpayers have noted that the state has been withholding more than necessary; these amounts are then returned to taxpayers in refunds the following year. To reduce the excess, the state plans to shave the amount it withholds. Thus the lower withholding would put more spending money in each paycheck -- but less in that refund.

Similarly, homeowners might double-check their own arithmetic for the governor's proposed property-tax credits. Many of them with mortgages, for instance, itemize deductions rather than take a standard deduction. And guess which category of taxpayers are not affected by the Hughes income-tax proposal? The itemizers. The property-tax credits merely allow certain taxpayers under the age of 60 to receive the same maximum credit now received by their older counterparts. As long as assessments keep rising, most homeowners' payments won't be any smaller than before, anyway.

None of this is to say that efforts to reduce tax burdens and still pay the state's bills aren't worth pursuing this year. But while Gov. Hughes and the legislators work on it, they'd be wise not to take too much credit for tax "relief" that some citizens won't realize and others will find difficult to distinguish from the ordinary workings of the Maryland tax system.