Inverted Stayman gets the partnership to 2M on 5M invite hands, but, in contrast to Keri, frequently has opener play the contract if that's the landing spot. Inverted Stayman works perfectly with the 5-4/4-5 major invite hands, unlike most other approaches.
Here's a simplified version of the ETM 06 Notrump structure (for the uber complex structure please click on http://www.bridgematters.com/etmnt06.pdf) using the terrific Inverted Stayman.
2C: Inverted Stayman, with all invites except 5-5+ in minors.
2D/H: Transfer, signoff or game force, can be just 4 card major if game force.
-- Responder's rebid of 2NT shows a 4 card major, or flat with 5, game force.
2S: Both minors, with a major suit singleton/void if less than a slam try.
-- Opener bids best minor if would decline a game invite, 2NT if would accept.
2NT: Transfer to Cs, signoff or game force.
3C: Transfer to Ds, signoff or game force.
3D: Game forcing Stayman.
3H/S: 4 in other major, singleton/void in bid major, game forcing.
4C: Transfer to Hs.
4D: Transfer to Ss.
Games: To play
2D: Any maximum, or minimum without a 4 or 5 card major.
-- non-jumps natural invites – opener will now show major if maximum
-- 3H/S: natural slam try with 4 card or longer major
2H/S: 4 or 5 cards in other major, fewer than 4 in this major, minimum.
-- Responder places contract
2NT: Both majors, minimum.
3C/D: Both majors, maximum, does not like bid minor (would pass invite in it).
3NT: Both majors, likes all suits.