An inconvenient truth
The Trib addresses what Ross Perot might call Pennsylvania's crazy aunt in the basement: an inequitable system for funding public schools. This is the reason why cutting property taxes is so difficult. Without reforming the school funding system--which puts the onus for funding schools on local districts, and thus local property owners--not only will you be unable to offer significant local property tax cuts, but you will continue to have vast inequalities among school districts.
Some other states have reformed their school funding systems after state courts have ruled that they were so inequitable as to violate state consitutions. But a similar lawsuit in Pennsylvania failed a few years ago. (Though the Trib article hints that the current lawsuit over Allegheny County's base-year system could have a similar effect. If the system is declared unconstitutional, and properties statewide must be re-assessed, taxpayers may demand state-wide reform.)
The other hurdle to reform in Pennsylvania is the state's strong tradition of local control--and many of the communities that value local control the most are the most affluent and thus have the greatest political influence. Districts like Mt. Lebanon, Upper St. Clair and Quaker Valley can raise taxes as much as they want, because many--though not all--residents can afford to pay them, and they moved to those places in the first place because they were willing to pay a premium for public education. Taxpayers in those places will not be happy to pay taxes to support school districts in places like Wilkinsburg, Clairton and Duquesne.
But until and unless the state tackles school funding reform, we will never have property tax reform. Because unless you change the way schools are funded, any property tax cuts would have to be matched by an increase in some other tax. (And it may have to happen any way.) As any politician will tell you, there's no percentage in that.