Collapse of Comcast cable deal may chasten Wall Street, for a while

By Diane Bartz WASHINGTON (Reuters) - Comcast Corp's failed bid to buy Time Warner Cable Inc is the latest muscle flex by U.S. antitrust enforcers and will likely deter chief executives from pursuing aggressive transactions as a way to spend excess cash. Comcast, which had barely convinced regulators to allow it to buy NBC Universal four years ago, folded under pressure from the Federal Communications Commission and the Department of Justice and scrapped its deal to buy its No. 2 rival on F