Phaheem "Anyway, does anyone have any articles or proof that e-brake + gear or e-brake only is better than the other?"
The proof I have is learning from others.
Automatic trans, or manual, the proper sequence for parking(as far as e-brake and gears), is to put the e-brake on 1st so there will not be any roll to put pressure on the gears, so when you're ready to leave(debark), you won't have any stress on the gears.
Also it's preferred to park in 1st gear(being the lowest and largest gear/cog, it has the least amount of chance to roll, or reverse if parked up hill).
There's no reason "not" to use both to park.
Don't get me wrong, I'm not saying I think ppl should do what I say. I'm just saying that from my experience and from what I've learned from other ppl, that using both will keep the roll aways from happening.
Once on my Jeep I was working on it with the engine running, so all I had on was the e-brake where as I was lazy and didn't chock it(being on a very easy grade), well the e-brake popped off(was a recall on it, which I never bothered to get done), it rolled back over the flowers and other soft vegetation and didn't hurt the Jeep, not so much the flowers. That's proof enough for me. I don't see anything wrong with learning from what others have learned, saw, heard, etc., why wait till it happens to me.