"The [amicus curiae brief of the U.S. Solicitor General with contributions by counsel at PBGC, DOL, IRS and Treasury] presents four arguments urging the High Court to read ERISA's church plan exemption to apply to employee benefits plans of religiously affiliated employers notwithstanding that the plans initially may not have been established by a church.... [1] 'Natural reading' ... [2] Context, history, and purpose ... [3] Consistent and long term application ... [4] No sound reason for radical re-interpretation."