The last time CBS decided to pull its O&O's off of Dish was also during NFL season, and so many people were PO'd, Congress was overwhelmed with constituents DEMANDING they do something about getting their local CBS station for, mostly, NFL. That was when Mel Karmazan was in charge of CBS. Congress did hold hearings with both Mel and Charlie testifying, but in the end Congress seemed more irritated with CBS for its pursuit of maximum money without considering their audience and the fact that they are a BROADCASTER with a FREE license to broadcast over the public airwaves with obligations to the public that Pay-TV channels don't have, and with the warning that if CBS and Dish could not come to agreement, Congress would seek legislative action on the industry, and it was clear from the remarks that it would be to the broadcast networks' disadvantage.
If Les is smarter than he has been of late, he would be a fool to pull his O&O's during NFL, but Les is ruled by avarice, so look form Les to inflict more damage on CBS than on Dish. Further, during the TW take down of CBS O&O, his O&O's local newscasts were decimated while the competition's local news ratings soared. Local news in those big markets are BIG MONEY. Frankly, CBS needs Dish or any of the MVPD's more than the MVPD's need CBS, and a take down of CBS from Dish could seriously revive the recently proposed local broadcast a la carte legislation. Personally, I think the local broadcast a la carte proposed legislation is a great solution: the broadcasters would decide IF they want to charge each subscriber for access to that local station, and the broadcaster sets the price. The MVPD's would make NO money from this arrangement. The MVPD's would simply pass along the entire fee to the broadcasters. Let's face it, no broadcaster would DARE charge on Penney for access via an MVPD, they way it ought to be since WE THE PEOPLE OWN those licenses. Of course, a few brave broadcasters may experiment with a fee, and perhaps the market would agree to it, but the nice thing is that the MVPD's are totally OUT of it, and the broadcaster have full control as to who will have access, paid or not.
Of course, Les would immediately negotiate a "reasonable" carriage agreement with Dish long before he gives Congress a chance to even introduce such broadcaster a la carte legislation, so we are unlikely to see any change with the current LIL payment model.