during his tenure as prime minister, čalfa was occasionally a target of criticism for his communist past. some considered this as a proof that the velvet revolution was unfinished or even "stolen" by people belonging to the past nomenklatura. presently, historians consider him as a "power behind the throne," who greatly contributed to the smoothness and speed of velvet revolution and the election of václav havel as president. he used his negotiation skills in critical moments against his fellow communist party members and talked them into compromises that were sometimes more radical the representatives of the civic forum had expected.