There’s a couple of things to consider here.
First, know this course is working your energy. No magick or energy working is going to be 100 percent safe. Horror stories from people having energy flow the wrong way are a thing. I recommend the story of Gopi Krishna, who has kundalini rising up the wrong channels that nearly killed him, and the work of Carlos Castaneda, such as The Journey to Ixtlan for examples… it’s normal to have enegy work bring up blocks and issues that have to be resolved.
This course is pretty tame. I found E.A. Koetting’s work after many years of other studies, in qigong and shamanistic techniques, I knew exactly what he was talking about and what state my energy system was in, most people don’t, they don’t study energy working, and run into trouble like the reddit poster did with no tools to understand or fix it.
Secondly, doing energy work kind of lights you up on the astral, and attracts entities that can and will mess with you, especially if you have energy leaks or imbalances they can leverage. This is sometimes called “opening a door that cannot be closed”. It can, but again people sometimes run into issues they didn’t even know could happen.
I would suggest, before starting any work like this, making sure your “spiritual hygiene” is on point and your protections are up. This is really the same idea as the old grimoires that told people to be chaste and pure for x days before ritual. You want a nice clean space and a clean system for best results without attracting unwanted energy.
We have some tutorials on that if you’re interested.