ICUS is a tool used by particular companies to hire Pilots without the required experience. They then pay less than what an experienced Pilot will work for (cause they are grateful to get a position they are not qualified for) and offer them ICUS until they meet the minimum regulatory standard, bonding them for the privilege. Generally these guys are hired as FOs with the lure of future ICUS to keep them in order. Don't want to rock the boat, might miss out on ICUS!
ICUS - a regional airlines poison chalice.