I don't see Hearns coming out to get into a shootout with Trinidad. He is more likely to box him. Trinidad didn't 'start slow' as much as he took his time and, if you pushed him, he could take his time pretty immediately.
I'd pick Hearns. Tito would have a real puncher's chance, though. If they go toe to toe either guy could ko the other. If Hearns decides to be the Motor City Cobra he wins a UD. I'll pick Hearns by UD
Hearns might knock Trinidad out cold. Stoppage round 5 maybe 8 if Hearns wants to carry it a little bit. Trinidad would be forever ruined
Hearns jab would b the key, Trinidad unlike most of Hearns opponents wouldn't need to stand tall just to reach Hearns , but his head movement was limited, that would prove to be his undoing against A fighter of Hearns caliber who could win a fight on the jab alone, (ask R.Leonard, W.Benitez) . Hearns would establish his jab, Hearns would respect Trinidad's speed and power and would patiently set up Trinidad. But sooner rather than later Hearns would fake that jab, or immediately follow it with that atomic missile of a right hand catch Trinidad cleanly stops him between the 4th or 7th rd.