This is the question that will determine whether the companies can close their $45.2B deal. It will collapse in Washington if Comcast and Time Warner Cable can’t persuade FCC commissioners and, to a lesser degree, antitrust regulators that the No. 1 cable operator and owner of NBCUniversal won’t have too much power to determine industry winners and losers, and set prices, if it also owns the No. 2 cable company. Execs hope to head that off by arguing that pay TV is highly competitive, and by making some specific promises upfront. For example, Comcast says today that it will extend to Time Warner Cable systems the net neutrality commitment it made to win FCC approval for the NBCU acquisition. It vows to offer “affordable standalone broadband service” in TWC territories. Comcast says that TWC’s regional sports and local news channels will be available to other pay TV distributors at reasonable prices with a right to arbitration in case of a dispute. And it will expand public interest programming including local news and children’s fare, and will guarantee carriage of non-commercial educational TV stations even if they give up their broadcast spectrum — something the FCC wants to reclaim and auction to wireless broadband providers. “In today’s market, with national telephone and satellite competitors growing substantially, with Google having launched its 1 GB Google Fiber offering in a number of markets across the country, and consumers having more choice of pay TV providers than ever before, Comcast believes there can be no justification for denying the company the additional scale that will help it compete more effectively,” EVP David Cohen says.