I think it does. "Since 2000 heavy trucks have" tells me "2000 heavy trucks" did something and I'm going to read what that something caused. It's only when I

I think it does. "Since 2000 heavy trucks have" tells me "2000 heavy trucks" did something and I'm going to read what that something caused. It's only when I get to "and similar gains are projected over the next few decades." that it's clear the author meant "Since the year 2000, heavy trucks have". It's a garden path sentence because the initial interpretation while you're reading it is incorrect and you only realise this when you get to the end and reprocess the start. If the author put a comma there, it would be clear on first read: "Since 2000, heavy trucks have".