Another tip from Martin:

After sliding in the chosen card into the gimmick in the middle of deck, then fan through the cards to show that the card is actually in the middle -- no need to get a break on the card. Close up the deck completely. Then do a Charlier cut. The cards will automatically break at the gimmick. Then just complete the Charlier and the gimmick will be on the bottom. This saves doing the half pass and again gives the illusion their card is further lost in the deck... and even the magi does not know where its position is.

These tips are for The Hawk gimmick.