This would certainly be suggested by the two facts that a) continuous enemy fire reduces the percentages at a steady rate, not an accelerating one and b) the severity of hull damage suffered in shields-up hits is seemingly independent of the percentages.
It's only when shields "collapse", as in ST6, that hits suddenly begin to pierce the hull unopposed. Powerful hits against minimal shields collapse the shields first and only then hit the ship in e.g. "Q Who?". I don't recall any blatant counterexamples at the moment...
Apparently, it's very difficult to damage the shields, that is, to do damage to the shield machinery. Rather, one only manages to drain the shields, but if firing ceases, the shields tend to recharge fairly quickly if there is power available. Thus, "regenerative" might be a general description of all Starfleet shields as they have behaved like this ever since TOS. Or then the same evidence could be used to support the argument that "regenerative" must refer to something else than the simple ubiquitous ability to regenerate, in which case the analogy to regenerative brakes begins to sound pretty good.