The Limits of Scrupling and the Adoption Act of 1729: the PUP Task Force's Historical Problem by Toby Brown
Brown explains the historical precedent of the scrupling that occurred in the church in 1729 as it is misapplied to PUP.  Historically, "Scrupling was only allowed on article that were 'not essential."  Nov/Dec 2005 Theology Matters  p.13