At the same time, I recall reading John Young's ideas for an "advanced orbiter." He wanted features like thrust termination on the SRB's and canards on the orbiter for better control on approach & landing. The former idea is idiotic, as thrust termination (blowing the nose caps) would likely rupture the ET and kill the crew. Canards aren't such a bad idea, but it's not easy to see how you could stow them for re-entry without adding a lot of mass.
there were other crazy "Ideas" would likely rupture the ET:
like put SRB segments or a Titan-II stage under the ET as "add-on Booster"
LBM 4 Titan-II tanks with total 159t fuel and 2xAerojet LR87-AJ-11 engine with total 200 ton trust
total weight 180t LBM ignition 5 sec after Shuttle liftoff
+5 tons payload for USAF mission (from Vandenberg AFB?)
another was to build Additional fueltanks inside payloadbay for the Orbital Maneuvering System
source: German space book
"Die Grenzenlose Dimension der Raumfahrt: Band 1"
by Harry o. Ruppe, publish 1980 ISBN 3430178847
page 647 - 640