Time management protocol question

I’m working on a time management/productivity protocol and using some of the videos from the Urge Jar and Weight Loss sections to help me understand the mindset and mental tools I need to utilize. In one of the videos, Brooke talks about protocols and says that when it comes to weight loss, you should stick to exactly what you wrote down. If you have green beans on your protocol and you don’t have green beans in the house, don’t substitute broccoli, go out and get green beans because it’s about your relationship with yourself and doing what you say you’re going to do.  I have trouble applying this concept to my day where stuff comes up and I find it extraordinarily challenging to stick to my plan. How would this concept apply to time management (or does it?)

Also, Brooke has said you should decide ahead of time how long something will take and then make it take that long, but I really struggle with this as well. I think something can get done in 10 minutes and it winds up taking 30, which throws everything else off. Should I give myself more of a time cushion? Trying to get everything done as quickly as humanly possible feels stressful to me but maybe there’s a better way to think about it?