Here are the problems: 1. Use of lubrication. If there is sliding on the skin, you are not engaging the superficial layer of fascia.
2. Quick and aggressive "raking" on isolated areas of the body. You can't achieve Myofascial Release with speed. The fascia, just as the gadget's name describes, is being harmed (blasted). It is being torn, not released. The web is no longer intact, it is broken. The fascial web is everywhere and when you address one area, you affect every area. So, if you think there is one spot in your body you can punish for misbehaving, you don't realize that every fascial fiber in you reacts to this by squeezing to protect you from the attack. You are eliciting the sympathetic nervous system response. Myofascial release happens during the PARASYMPATHETIC response.
3. Regarding the claim that skin shows less dimpling afterward. This is temporary. The inflammatory response occurs due to the trauma experienced by the assault. As the fascia is torn rather than released, it repairs just like scar tissue, thicker and more resistant. The opposite of your intention. Symptoms of pain, poor elimination, swelling, poor lymph flow, poor circulation and autoimmune dysfunction years down the road will be considered random and inexplicable with no understanding that what you did with that hideous gimmick years ago created the problems you have down the road.
4. Comparing it to Rolfing. This is accurate. Myofascial release therapy differs fundamentally with Rolfing about this very thing. We wait for the body to soften and melt, giving us permission to sink deeper, allowing us to get at the deeper (older) injury or trauma. We NEVER tell you to hold your breath, grit your teeth, or just bear down and endure any pain. If you brace, that is the opposite of what we are trying to elicit. We allow for the emotional release that comes from letting go in this way. The clench may have happened when you were a kid and the body needs to feel safe and know that moment is past and there is no danger in letting go now. Rolfing applies force, uses lube, and asks you to just breathe through the pain.
I can go on about this, but you get the main points. If your answer is "I'm going to do it anyway." You join the many who keep myofascial release therapists in business.
Look into the long-term effects and stories and pictures of folks who got liposuction. There's a blast from the fascia past.