This felt a bit like a "girls ep" to me -- it seemed like the vast majority of the scenes had one of the two girls (or both) in them. Maybe it was just that Jo had the B storyline and we can no longer (apparently) see Danny without Lindsay that did it for me. Okay, so my real complaint was not enough Flack or Danny. I love those two characters, especially together. Danny in general seemed MIA from the episode -- a condition that had me concerned with the move to sergeant. We'll see how it plays out, I guess. Spoiler free, but predicting he chooses to go back to the lab -- they already hinted that he's "missing all this" about 3 minutes into this ep.
As for D/L "lunch" moment. I am not aware of cop life but really, what kept her from going to lunch? People get lunch breaks when they work and it wasn't like Mac was standing behind her shoulder saying, "You better stay or I'll beat you." Wonder what kind of hours real cops have as for lunch break and such. Idk it frustrated me rather than being a cute moment.
Danny is a sergeant, means he's back to beat-cop hours. 5 on 2 off 5 on 3 off, eight hour shifts. Much more regular than the CSU is portrayed as having (they answer calls at all hours, apparently). He appeared to have gotten the 'first watch' of 11p-7a, which is not ideal but better than 'third watch' (does NYPD use 'watch'?) which runs 3-11p. Maybe I was confused about what time the body was found, so he did get 3-11 which makes the scheduling issues a bit more realistic. At any rate, he'd get a one hour lunch that he calls in to dispatch. Once he's called it in (before going to meet Lindsay) he's committed to that one hour. Still, as portrayed in this episode, Danny made the time to see her but Lindsay did not have (or take) the time to see him -- makes her complaining about never seeing him seem a little like blaming the wrong party, imo. At any rate, his hours would be pretty regular unless he's taking the maximum OT every month too. 3-11 if Lindsay was actually on days would make for some serious lack of 'awake time with spouse' though. Great for childcare costs, however.
Random note/question: why does every tv cop work from the 12th Precinct? At least on this show and Blue Bloods, it's all the 12th. Which, yes, I realize is a safe number that's no longer used by NYPD but they made up the 55 for Third Watch, surely they can get more creative here too. I know for sure that 11, 22, 33, 44, 66, 77, 88, and 99 are not used (NYPD does not use repetitive call numbers) and I think there are others, too. Maybe the prop dept only has lapel pins in '12'? Flack worked that precinct in his flashback, so did Danny (last season) and now Danny is there again. Also, the precinct Flack is seen to work out of is the twelfth. For the really inane trivia seekers the 12th once covered the area around Little Italy, now into Chinatown -- I think the old precinct house is on Mulberry? Definitely the Little Italy neighborhood though. So Danny has apparently been assigned a Manhattan precinct (even if it is a fictional one).