You're already reworking the song in your head, aren't you? The stress could just as easily fall on the offbeat through the verses, and a second guitar definitely comes in early with some high-up staccato chords. Actually, the first two bars of the song—the muted notes that play while the video pans around to show a diving center somewhere in suburbia—definitely have a ska-like feel to them. It wouldn't have been too big of a leap.
Sum 41's "In Too Deep" absolutely could have been a reggae song. According to Fucked Up guitarist Ben Cook, it very nearly was.
Cook—who also fronted the hardcore band No Warning and makes '80s-inspired pop music as Young Guv—was a guest on the Blink-155 podcast last week, and he closed out the show by talking about Canada's fart-joke-lovingest sons. Cook said that Greig Nori—who fronted Treble Charger, managed and produced Sum 41 for a while, and played alongside Cook in No Warning—wrote a "shitload" of songs for the band early on. "In Too Deep," he says, was originally Nori's song, and he recorded a version of it with Canadian reggae artist Snow.
"I've heard it—it's amazing," he said. "One of [Nori's] early ideas was to mix pop-punk and reggae." You'll have to listen to the end of the podcast above to hear Cook impersonating Snow's verses and Nori's choruses. And you should, if only to confirm that, yes, "In Too Deep" absolutely could have been a reggae song, it makes perfect sense, and if a version of the song still exists, there's no reason for the world not to hear it.
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