In order to seduce his junior assistant, a conceited inventor exchanges bodies with an attractive stranger. But when she rejects his advances and he loses control of his research, he must attempt to reverse the exchange or else face the rest of his life living someone else’s.

correction: I meant to say the "majority of produced film's loglines "

-- when I read through the loglines of produced films, I don't see that formula very often.

The formula works, which is probably why it's popular here. I don't know. Maybe it's because we've gotten so used to reading each other's loglines, we've all sort of gotten into that same formula.

The stories you've been coming up with are very unique. I think the packaging should be unique as well.

I mean, a majority of produced films could be broken into that formula, but, in reality, they probably aren't.

I hear what you're saying - I use the same structure again and again. But what is the alternative? By its very nature a logline needs to be set up in that fashion. Every logline on this site (if written correctly) reads like this:

When (the inciting incident happens), a (flawed protagonist) must (achieve this goal) before (whatever the stakes of failure are occur).

The optional conjunction (step 3) is included when the goal of the protagonist changes at the midpoint (for instance, in this story, the first half of the film is concerned with him trying to sleep with the girl, the second half is him trying to reverse the damage done. Or in Avatar - trick the Na'vi into moving, save the Na'vi. Or Toy Story - get rid of Buzz, get back home).

So what's the problem with this setup grammatically?