Not brewing all at once

Has anyone ever separated their brew day? I did this the last time I brewed, and as I drink while typing, I am not noticing anything off about my AM Ape, a breakfast stout.

Further description of the day; When my daughter went down for her nap I got started. She slept just long enough for me to get the wort flowing from the mash. I kept check on that after she woke up, and when it was done, I covered the kettle. It then sat while we played, ate dinner, gave her a bath and put her down for the night. After that I began the boil, and finished off as I normally would. The biggest difference was the time I finished at which was about 11pm instead of the usual 2am. I like that very much.

It has me wondering if I might separate the process even more. For example, mashing Friday evening and boiling sometime Saturday or Sunday. What do y'all think?

If you're going to space it out, you want to at least start the boil, because grains are teeming with lactic acid bacteria. Boiling kills them off (mostly) and prevents you from doing a sour mash, the beginnings of a tasty Berliner Weisse or Sour Mash Whiskey, but not a good beer of any other style.

So if I don't have the time, I should boil it for maybe 5 minutes and then cut the flame?

A beer like a breakfast stout will have a lot of flavors that can mask off flavors, I you where to apply the same method to a beer like a munich helles you might detect some issues. I'm sure there are people out there that do it, but I would not recommend breaking up your brew day for more than a couple hours let alone a day. It is possible to greatly reduce the time of your brew day with pre-prepping and organization. But if you don't have time to brew one day, I think it is best to just brew another day when you have the time.

i mill the grains, fill the HLT, make all of the electrical and gas connections the day before i want to crank out a brew. the next day i can have the beer sitting in the fermentation fridge in about 4 hrs then i take off for work. the clean up is the part i let sit until the day after or beyond if i'm really busy. i have my 5 and 3 yr old girls swirling around me the whole time and i so wish they would nap but they won't. i "save" time with the prep work and letting the cleanup go for a day or so but the actual brewing process i don't stop. i won't let wort sit in the boil kettle or the mash in the mash tun beyond what is needed. in the past i have let wort sit overnight and pitched yeast in the morning with no ill effects but now i like the process to go from start ti finish in one continuous flow.