I take your point, but allow me to advocate for... let's call it an alternate devil.
Jill is, as you say, skittish and superstitious. She has endured a number of unpleasant dates by men ranging from immature to insufferable. It seems she has come out of this ordeal believing that she'll know her Mr. Right when he sweeps her off her feet in storybook style. The MC ticks the early checkboxes, only to fail Jill's secret test of character when he doesn't recognize the unique fluke of destiny that would have allowed her to defy Tybalt properly (however she defines that). At that point Jill switches from looking for signs that the MC
is the one to looking for signs that he
isn't. Hence her irritation when he claims to want to spend time with her, and her disinterest in his later heroics. (And by extension, why the MC DOES sweep her off her feet if he goes on that date; his behavior is consistent with the romantic tropes Jill expects).
In and of itself that's not an unreasonable interpretation of the character. It's just that I *hate* that character. It makes Jill little more than a cardboard cutout, every bit the naive princess cliche her initial portrayal took such pains to avoid - or so it seemed. Moreover, it implies that we're going to spend Season 3 watching the MC and Jill blunder through every obvious relationship mistake in the book. I'm not sure I'm up for that, especially since I doubt Jill's branch will be the only one to suffer these sorts of setbacks.
That's a big part of why I'm so down on Zoey's flashy return; she's a lazy way to make the MC doubt his choice rather than allowing us to explore the consequences of that choice in a more open-ended manner. This sort of thing risks obviating a lot of our choices because the one choice we truly care about is denied us. We'd be forced to watch the MC crawl through "baby's first romance" for the next 4 years until we're finally reach the endgame. Definitely not what I'm hoping for after all the effort DPC spent
forcing us to make what turns out to be a premature choice.
That's why I said I prefer to chalk Jill's behavior up to bad writing and ignore the larger implications. It allows Jill to be an interesting, intelligent woman, someone who struggles with her insecurities without taking it to the point of delusion. And it keeps the focus on our choices rather than calling attention to the fact the MC is on rails. YMMV, but I don't think BaDIK's pacing or college antics work nearly as well if we need the MC's relationship to hit rock bottom before it finally goes anywhere.
I have too much respect for DPC's craftsmanship to think this is a bug. Even if it was, the furor over the choice back when Episode 6 dropped should have clued him in by the time he was writing Episode 8.
If Jill had asked the MC on a date before Sage made the request, I'd agree with you that both options are viable. But with Sage making the request first (assuming you call her), the only reason to ditch Sage is metagaming. In the real world, any sane MC would just explain to Jill that he's already busy and ask for a rain check. That's as basic a socializing skill as there is.
I sincerely hope not. As I implied above, I think the MC's newly minted relationship will be tested this season and ultimately found wanting. But I also think we'll either be able to save/rekindle it at the last minute or start a new, mature relationship with a different girl in Season 4. (So technically I don't expect Jill's stinging rejection to be the final word on the matter.) That's how things look to me at the moment - which is tremendously frustrating, but at least it offers an eventual payout.
But if you're right and this whole thing is going to be a bunch of shaggy dog stories about how the MC's choices are unrealistic and can only end in abject failure, I think I might actually prefer the ending of Acting Lessons.