bondview2.c reads crouchDown = insightaimmode && (buttons & (D_JPAD|D_CBUTTONS))
(5318/5579): crouch is C-down WHILE IN AIM MODE, never the B button. M3's
IA_CROUCH -> GE_CONT_B (and the CrouchMode=1 latch) was inert, so crouch
never fired in the GEPD layout. Hold + latch now emit GE_CONT_D (0x0004).
N64-faithful side effect: S (IA_BACK, also C-down) crouches while aiming.
User re-test: aim (RMB/Left Shift) + Left Ctrl; hold or F10 Toggle.