Granted too many league bowlers feel that a ball that hits the 1 and 3 pins (right handed) it should strike and if it doesn't then they were robbed.
5-7, 5-7-10 and 8-10 are bad shots that deflect way too much when they make it to the 1-3, hence they are not good shots.
I'm sure any long time bowler has released a shot and it felt like a million bucks, right speed, right line, right amount of turn and 9 times out of 10 times it strikes. But there is that 10% that either thru conditioner carry down, pins off spot, pattern break down, etc. they simply don't strike and can leave an occasional ugly split.
Belmo's case I thought he wasn't playing the lanes correctly trying to slow hook them, he could have played the same line the winner was but chose not too. The line he chose lent himself to leaving the 7-10 with shots that felt good to him off his hand but simply came into the 1-3 a little late at the wrong angle. I don't believe they were poorly thrown shots just bad results.