AIDE TO CARTER GIVES PLAN ON TAX REVISION
Laurence N Woodworth, Asst Sec of Treas for Tax Policy, in briefing for newsmen, outlines principles Carter Adm hopes to incorporate in tax reform proposals next fall; all income--personal, corp and capital gains--should be taxed at same rate; divds should be taxed only as corp profits, not also as personal income; persons with comparable incomes should bear equal tax burden; Repr Ullman comments; Woodworth says no final decisions have been made (M)