RM-MN, you're a pretty sharp guy, but do everyone a favor and stop telling every new brewer that they should do an abbreviated mash. You may have good results from it being as you mill your own grain into a near flour state,
but most new brewers are using pre-milled grain that isn't that finely ground.
On your whole iodine test being negative at 30 minutes... You know you can get a false negative on that test, right? If you're using conventionally milled grain, you can have a negative result at 30 minutes, too. But stir your grain bed and check again... You'll show starch. That's because it takes time for the saccharified sugars to slough off and expose new starch if you're not stirring or recirculating the mash. Most BIAB brewers aren't. A longer mash gives the time needed for that to happen. Also, most new BIAB brewers aren't working with their water chemistry and mash PH. That can lead to a further slowdown of conversion which again, will cause issues with a short mash.
I know you mean well and all, but it seems that every other post from you is, "HEY GUYS! YOU ONLY NEED TO MASH FOR LIKE 45 SECONDS!"