I've been teaching rolling for over a decade now and have taught hundreds of people how to roll. So I want to share my philosophy with the acknowledgement up front that there is no single answer. Other people may do things differently and I'm not saying that's wrong. But I've learned a thing or two in my time and seen a lot of paddlers rolling (or trying to roll) in different environments. I have specific reasons for doing the things I do.
The sweep roll I teach has several benefits over other rolls. It is gentle on the body, it doesn't require great flexibility or strength, it keeps the shoulders in a protected position, it will work with any type of boat. The only real downside is that it is hard to learn - you have to do several different things with your body with just the right timing. While upside down. Under water. Yeah. Once you get it it's easy, but that may take a while.
And I explain that to my students. I get their buy in. I tell them up front it's going to take time. But I explain why and that makes it OK. It's important to give student success to keep them motivated, but when that short term success comes at the cost of slowing long term success I don't think it's worth it. I find other ways to create success - mostly it's just an attitude thing. I've had students take four or five sessions to get their first roll and they kept working at it because they knew it was worth it. They always left smiling.
This is the point where people often want that feel of success. They want to get up. But if you give them something to accomplish this that is different from the core muscle movements it will create a crutch that's hard to break. If you hold their paddle it gives them support that their body learns to rely on. If you extend their paddle it creates leverage they can push against (not something you want or need in a proper sweep roll). If they finish on the back deck they will get used to it - and being on the back deck in the middle of big conditions is not where you want to be. If they can muscle the roll that means they are straining muscles that can lead to injury. A proper roll is effortless.
So I stay focused on the proper technique and generally step back instead of pushing forward. I have students repeat the initial individual movement exercises. I have them practice the timing while upright. It doesn't give that same feeling of success, but it does give the same muscle memory for a proper roll. If people know that they are on the right path and that they are moving forward, if slowly, they will continue down it. And the reward when they reach the end is worth it: a solid roll that works when it's needed, doesn't lead to injuries, and inspires confidence in paddling. It takes time. It takes patience. It takes perseverance. From the teacher and the student. That's how I roll.