I'm not sure who "them" is referring to when you say people can be abusive.
So traditionally in kink days of old, mainly in leather communities it was fairly common to start off as an S type and work your way up. There are benefits to this method however its not entirely necessary in my opinion. Forcing one to take on a sub role just to get the understanding is pretty extreme and just as most people who are full sub aren't comfortable being the Dom role it works both ways so why would one who's strictly dom want to sub? Now what was suggested above is great advice. I follow a similar practice as well. Testing out ties, floggers, canes, chem play, clamps, wax, (wax is a huge one for safety) etc. Lots of things you need to develop a feel for so that you can do it properly and not injure the one you're with. Also making sure to test things on same parts that you plan on using your S type. For example me hitting my hand is far different from her inner thigh. This helps keep you aware and the sub safer.
Now, do you need to do anal on yourself to understand how it works? Well no not really but you should get advice from those more experienced both D and S side through the way of forums like this, mentors, demo nights at local clubs, other resources. Be informed, do research, and be man enough to say "I don't know or I need help"> Ultimately your sub is your responsibility to care for and keep safe, she needs to be aware of the risks yes, but times of subspace will make it very hard for her to make that call and at that point its all you having to know whats best in the situation.
Anything unfamiliar or "first times" for you both take very slow. Better to build up slow and safe than end up injured. Seen way too many new subs taken advantage of and injured. Impact done wrong injury, anal too fast too much and soft tissue torn, waxplay burns and melted skin , lots of nasy things come from lack of knowledge.
Good on you for asking like you did, be one of the ones who comes out as a "good dom"
