Gov. Nathan Deal’s merit pay proposal for teachers runs the risk of becoming the hoverboard of education, a smooth way to advance our goals but apt to explode from poorly made parts.

The incendiary issue will dominate the opening of the Legislature next week, according to House Speaker David Ralston, R-Blue Ridge. Meeting with wary teachers in his home ground of Fannin and Gilmer counties over the last few weeks, Ralston said Georgia is not ready to roll out a fair and equitable pay for performance model.

“The case has not been made to me for merit-based pay,” he said. “I’m troubled by how you quantify and measure and get to the point that the concept wants to get at. And I am hearing this is going to have some impact on recruiting teachers.”

Ralston relayed how a veteran teacher who hoped her child would one day follow in her footsteps told him her “daughter has now quit talking about wanting to be a teacher and she’s quit wanting her to be a teacher.”

Gov. Deal plans to push for pay for performance as part of a broad package of education reforms that also features a new funding formula. Deal’s conviction that student academic performance should influence teacher pay is shared by the Obama administration and outgoing U.S. Education Secretary Arne Duncan, who tied test scores to teacher evaluations in their Race to the Top grants, from which Georgia received $400 million.

Merit pay counts as one of those education ideas — and there are many — that sound perfectly reasonable until field tested. Not long ago, bonuses were touted as an incentive to push teachers to higher levels of instruction. But a RAND study out of New York and a National Center on Performance Incentives at Vanderbilt University suggested many teachers were already running as fast as they could and bonuses made no impact on student achievement.

Nor is merit pay a new concept. Donald Gratz, author of “The Peril and Promise of Performance Pay,” quotes a 1907 lament from Edmond Holmes, Great Britain’s chief education inspector, who believed test-based performance pay was leading teachers to engage “in laying thin films of information on the surface of the child’s mind, and then, after a brief interval, in skimming these off in order to satisfy himself that they have been duly laid.”

A typical argument for merit pay is that other industries embrace it, but that doesn’t mean it works. A 2010 RAND review of pay for performance initiatives in transportation, child care, education, emergency response and healthcare found limited effectiveness. When it was successful, RAND identified several critical components: Evaluation measures were clear and easy to observe; employees had some control over inputs affecting their job performance, there were not competing interests and there were enough resources to design and support a good performance-based reward system.

Merit pay, at least as now proposed in Georgia, lacks those elements. We have brand new state tests, the Georgia Milestones, so we don’t know yet whether the scores connect in any way to teacher performance. About 70 percent of our teachers are in classes without state standardized tests, including PE, civics, chemistry, art and music. The state’s solution of allowing each district to create its own Student Learning Objectives to evaluate such teachers remains a muddle.

We don’t have scales that weigh a teacher’s dedication, creativity, and commitment. Nor do test scores reveal the valuable and often life-changing work teachers do, believing in kids when no one else does, mentoring younger colleagues crushed by the challenges, educating parents who never finished school to dream bigger for their children.

Until Gov. Deal and the Legislature can address those deficiencies — and there may well be solutions — they ought to move slowly or risk going down in flames.