The summary doesn't say anything about Tai and Meiko. There are two users who talked about seeing Part 5 or something, and one of them is whom Link Guy quoted his/her summary in the above posts. S/he's talking about seeing heavy shipping moments of Tai and Meiko and few of Yamato and Meiko.
There are users who pointed out that it seems more like Meiko featuring Hikari Part 5. It centers more around Meiko.
I think this user that I'm going to quote speaks for the majority of the audience concerning the shipping moments with Meiko :
" With that said, I hope the Tiachi and Meiko moments are not as big as Jay describes. While I do have an indifference to that particular ship, my issues more stem with how late it came in tri.'s narrative. I would rather them not have any romantic moments beyond simple teasing, which to be fair to Jay's description, it doesn't really seem much apart from teasing. Which, yet again, feels like it comes out of nowhere. "
I want Tai to be left alone rather than giving him Meiko just for the sake of pairing him up.
I think all stuff is in general I mean Tai helps Meiko so is good for his character and progress or for Meiko is more good for her character to fit in the group, this more than the shipping.
I just fined giving Tai a new "love interest" after teasing him with Sora for the about half of the movies to be in poor taste. PERIOD
Agree with you giving the boy a lover is good. The only bad thing is the writing. Possible off the camera is the better way to end this.