Got an interview with BP and this round is an "On Demand video interview" where I video myself answering questions and send them in.

First, is this just a brush off? Other than being clean-cut and making sure to answer the questions intelligently, succinctly, and enunciate any tips? One is not expected to put on a suit & tie for this are they?

Make sure your internet connection is solid. No distracting background. High quality video camera.

I'd go no less than dress shirt and tie.

These are an easy way to weed out and get better questions than an HR phone interview.

This is a terrible way to "interview" in general. I don't let my HR do this.

Honestly, ify company did this, I'd be perfectly happy if someone popped onto video wearing a t-shirt, answered the questions, and sent it in. At least it's authentic and not fake polished BS.

You have to remember, this is a competition. You dress as if you are in person for interview. Like other said above, practice making eye contact in camera with a professional, non distracting background. If you choose to do this half way, others are giving 100 percent. Why waste your time with not giving your best if you are really interested in the job.