(July 29, 2016) -- At a key point in the film Casablanca, Humphrey Bogart and Ingrid Bergman scramble to catch the last train out of Paris before the advancing Germans close off the city. Something similar is going on now in the merger world, as dealmakers try to get the last problematic transactions through the agencies before antitrust enforcement may tighten up in the next administration. This is illustrated by the proposed merger of paint-makers Sherwin-Williams and Valspar, now playing the roles of Rick and Ilsa....