Rendell's very public swing through the Capitol a year and a week after he left office raised some eyebrows. Other former governors and their aides said unwritten rules of political decorum frown on former chief executives taking public stands against successors' policies.
Echoing a theme sounded this month by Republican presidential candidate Newt Gingrich - who called President Obama "the food stamp president" - Corbett spokesman Kevin Harley labeled Rendell a "food stamp expert," and noted that the number of recipients doubled during the Democrat's two terms in Harrisburg. Harley said the asset test was necessary to prevent fraud.
"There is going to be an asset test" in the coming months, but the administration has not determined the threshold, Harley said, adding, "If [Rendell] doesn't think there is waste, fraud and abuse, then I have some federal swampland to sell him in Florida."
Under the administration's proposed plan, the bar is set to deny food stamps to anyone with more than $2,000 in savings or other assets subject to the rule, or more than $3,250 for people who are over 60 or disabled.
In 2008, Rendell dropped an asset test in response to the wave of people left jobless by the recession.
The former governor noted that applicants still face a "means" test of income, and that Pennsylvania has been cited by federal officials for its low fraud rate.
Figures confirmed by the Corbett administration show that the level of food stamp fraud in the state is one-tenth of 1 percent.
With the economy still struggling, reviving the asset test for some 1.7 million food stamp recipients could drive tens of thousands into deeper poverty, Rendell said.
While he said he understood the difficult budget choices Corbett faces, Rendell - careful not to personally attack his successor - said he would continue to speak out.
"This is not meant in a partisan fashion, but a plea from all of us to help Pennsylvanians," said Rendell.
Though most states eschew asset tests for food stamps, Corbett's Department of Public Welfare surprised critics with its plan to reinstate such a test in Pennsylvania.
That decision was laid out in a December letter to the U.S. Department of Agriculture, which administers the food stamp program. News of the letter, first reported by The Inquirer, drew strong reaction in many quarters. U.S. Agriculture Secretary Tom Vilsack is scheduled to be in Philadelphia on Thursday to discuss it with Mayor Nutter.
Former governors and their ex-staffers said it was unusual, even impolitic, for an ex-governor to speak publicly against a successor.
"It's unprecedented," said David LaTorre, a spokesman for former Gov. Mark Schweiker who also worked for Gov. Tom Ridge, both Republicans. "There is an unwritten rule for any governor: You never criticize your successor."
LaTorre said Schweiker may have appeared in the Capitol in his later role as president of the Greater Philadelphia Chamber of Commerce, but never "directly confronting the policies of his successor, namely Rendell."
Former Lt. Gov. Mark Singel, who served under Democratic Gov. Robert P. Casey, agreed that Rendell's appearance was "unusual," but said it was not out of character. "You can't blame Corbett for being sensitive to the issue," said Singel, who now heads the Winter Group, a lobbying firm.
Former Gov. Dick Thornburgh, a Republican who went on to serve as U.S. attorney general, said he could not recall going back to Harrisburg to address any particular initiative of his successor, Casey, after he left the governor's office in 1987.
Thornburgh said he might have returned on occasion to talk about things that didn't get accomplished under his tenure, nor since then - such as privatization of the state liquor stores and so-called "merit selection" of judges.
Contact staff writer Amy Worden at 717-783-2584 or firstname.lastname@example.org, or follow on Twitter @inkyamy.
Inquirer staff writer Alfred Lubrano contributed to this article.