Controversial??? Discussed, debated, theorized about, and bemoaned, yes ... but I've never seen a single heated argument about it anywhere and I've been heavily researching all things YouTube lately.
I think you're looking for cavities in the wrong end of the horse.
Length doesn't matter. To paraphrase Roger Ebert...
"No great YouTube video can be too long, no bad YouTube video can be too short."
Seriously, forget about how long your videos are. Instead focus on how good they are. Edit them down to just the good parts. Never add in filler just to lengthen them and, naturally, NEVER delete anything good from your videos. Do not worry about one of your videos being longer or shorter than your average video. Again, just focus on quality. If you can give quality, people will give you their time. I've seen very popular vlog videos that last longer than two and half hours because they're just that good.
Now if your show uses a format (like how my YouTube game show will), what you can do is work on distilling your format down to just the essential good parts.
1) Do a quick tease. Don't do a burlesque show version of a tease. As long as it would take you to blow a kiss, your tease should be that long.
2) Keep your intro to at most 2 to 3 seconds. Or better yet, just slap on a watermark in the lower right corner of your videos ... which you should do whether or not you do an intro.
3) Don't give any video time to your end credits but silently subtitle them near the end of your video. And if you just absolutely positively have to have an end piece (such as "Please please please please please subscribe to me!!!!"), use your video editor to at least speed it up as fast as it can be clearly understood.
And if you're a gaming YouTube show, NO ONE wants to watch you run to anywhere. Jump cut to or, better yet, fast forward to where the action is. Fast forward is better for those who want to know how you got to where the good action is in the game. No, you yapping away while you are real-time running somewhere doesn't make up for you forcing your viewers to watch you run somewhere. That and never stop talking. You might think you're doing some super cool combo move that your viewers will wet their pants watching you do, but you're only kidding yourself ... or feeding your ego. Your viewers are watching you play a computer game to: 1) learn how to play that game better themselves, 2) be entertained by your witty banter, or 3) ideally both.