-Change option -R to accept lists of headers and parameters:
--R h1,h2,h3:p1,p2,p3
-Allow * and exceptions:
--R h1,h2,h3:*,-p1,-p2,-p3
--R *,-h1,-h2,-h3:p1,p2,p3
--R *,-h1,-h2,-h3:*,-p1,-p2,-p3
+Never decode subparts of multipart/encrypted and multipart/signed messages but
+allow processing of headers of the top-level part, ignoring the top-level part
+with -I, aborting it with -e or saving the part or subparts with --save-*.