To show on his spreadsheet what happened tonight, I'd stack numbers in the +12/pmps column like this:
12=158
12.5=191
That tells you that at +12 he was 158, and that you waited 30 minutes until he was 191 and that's what you shot. If you'd stalled longer, you could've add a "13=xyz"
Good job sticking with all of it tonight. You did great! You won't have to do this forever, in fact, Oz is having a great response to the insulin. That nice flat cycle you got tonight is perfect.
The main thing with shooting a number lower than you've shot before is to get a +1 and a +2 - you want to make sure that a cat isn't diving. Some do. While Oz dropped by +2, i wouldn't have called it a dive, he just went nice and slowly.
Experienced people will shoot everything over a 50 as long as their cat is eating and they are able to monitor. For now, you're not to that point yet, but if you're around tomorrow, you're probably fine shooting in the 150-ish neighborhood. Here's a post I did recently for someone else about
Shooting Low. You want to get to the point where you can do that as soon as possible. You don't need to read it tonight, but if you're faced with the situation in the morning you can look then.
I'm headed for bed. I think you're fine tonight. Sleep well!