I'm surprised there was no mention of accent. For their example "It’s tough when you’re trying and finish(ing) an assignment under pressure.", I can't help but hear "It's tough when you're tryna finish an assignment under pressure.", which really is more like "trying to" than "trying and finishing".
Yeah if I wrote "tryna" out nicely, I would spell it "trying to". So but that's my accent accounted for. There are a lot out there.