Jess R. Phelps (Historic New England), Preserving Preservation Easements?:  Preservation Easements in an Uncertain Regulatory Future, 91 Neb. L. Rev. 121 (2012):

While federal tax deductions are an important tool for organizations
operating easement programs, recent IRS enforcement activity has called
the future of this incentive into question–at least as currently
constituted. Even if these incentives continue, the presence of
continued regulatory uncertainty will make federally subsidized
easements less viable unless enforcement activity decreases or
easement-holding organizations begin to change how they protect
privately-owned homes. However, these challenges provide
easement-holding organizations a chance to step back and evaluate their
accomplishments of the past thirty years. Many significant structures
have been protected, but preservation easements lag far behind in
numbers, impact,
and public
awareness when compared to land conservation efforts. The public has yet
to fully “buy in” to the concept of preservation easements and are
suspicious of efforts to provide funds to protect private residences.

For this perception to change, easement-holding organizations need to
fundamentally re-evaluate the role they play within the preservation
movement and determine whether a larger role is possible. There are a
variety of ways that easement-holding organizations can shift their
thinking and practices to expand the benefit provided through their
programs. Similarly, there are clear alternatives to securing the
preservation of significant historic resources via reliance on the
federal tax incentives. In the end, the efforts of easement-holding
organizations to respond to these challenges and reimagine the
possibilities of preservation easements will go a long way toward
fulfilling SPNEA's original vision of obtaining control of the most
significant historic properties and “let[ting] them to tenants under
wise restrictions.”
Perhaps more importantly, these efforts can also expand upon this
vision to protect the underlying stories and preserve a more meaningful
spectrum of our collective architectural heritage.