I was in situation #1 a few weeks ago. Start with 1st 20, leave a 6,7,10 split. I went for the conversion, just missed 8 out. Next three shots left 10 pins and a 4,9 pocket split. The previous split line me up to convert the 4,9. Then someone told me if I get the last seven strikes I shoot 800 even. So I get the next 6 only to leave a 10 pin for the 799. My question is was I too careless going for the 6,7,10 conversion (In most cases I get the count especially on a string)or Was I justified for going after the conversion? I don't feel bad about the 799.