Hitting two is sexy, fun, and often the play we find over the board when we get a chance, but it's very wrong in this situation if you compare the risk/rewards of that play vs. simply buttoning up all but one checker. When you hit two you give your opponent 20 numbers to hit you back with immediately, and when you get hit, you simply don't like it. When you don't hit, Red only get's hit 14 times. And when you don't get hit you probably have a double and a drop in most sequences. If you don't get hit after hitting twice, you still have two blots to clean up, so you may not even have a double depending on what White rolled.
What if you do get hit? Of course you don't have a double, but when you make the better play there is only one blot and you have a much better chance of recovering and no immediate risk of another checker being hit as well. So in all scenarios, hitting twice is worse (but it is fun).