A potential course member wrote to me asking if the magic I teach in the course results in visible manifestations. He had read Lisiewski and others who claim physical manifestations are not only possible, but also necessary for the magic to be successful.
I've heard the siren call of that level of fundamentalism. I tend to think of the new Hermetic Fundamentalists as Grimoire Thumpers, with all the zeal and common sense you find in extremists of any belief system.
Look, when the spirits are present, yeah, you sense them. You might see something in your "astral" vision. You might smell them, hear them, or feel them press against you as they perform an initiation on you, tracing out seals on your forehead or whatever. you might even see them physically open the door, sit down next to you and spark up a bowl of fine imported tobacco. That doesn't mean that anyone else sitting next to you in the room will experience the same thing, nor does it mean that your ritual will be any more or less successful.
I've seen spirits. I look over and see darker or lighter "orbs" floating above the altar. Bune sits on the floor where my baseboard heater runs along the wall, with his long skinny knees up. I see angel faces appear in my crystal ball. I don't pretend any of this is something anyone else would physically see if they were present.
That said, my spouse sees stuff when I do magic. But it's not always what I see.
I've had magician friends tell me they followed the steps of the grimoires exactly, Lion Skin Belt and all, and they tell me they saw the spirits visibly. Great, but what about the results? No different than my own.
Personally, I suspect they had a stronger psychic image of the spirits as a result of the increased initiatory vibration attained through the creation of the Belt. I don't think a mundane person who hadn't been through the process of creating the talismans would see it. That's just my opinion. I don't think something that can't be photographed can be seen by the naked eye.
As far as I know, the historic accounts of magicians conjuring a spirits using the techniques of Reanaissance grimoires don't mention physical or visual manifestations, unless they used a skryer to see the spirits as Dee and Kelley did. Dee didn't see the visions Kelley saw. Benvenuto Cellini, a 16th century goldsmith and magician performed the magic of the grimoires of his time to conjure up spirits in the Colosseum. No one but the skryer saw anything. The other witnesses literally and figuratively shat themselves in fear when they felt the spirits arrive, but no one but the skryer saw anything.
So, since my own results don't indicate physical manifestation is possible, or more importantly even necessary, and historic accounts of magicians of the time of the grimoires I use don't mention physical manifestation, my stance is that sure, you may see something, but don't expect anyone else to. And don't worry if you don't see anything; results are the only proof that matters.