Yes, that's right.

Acutally, I hedged. I have had 100 percent success (after practicing the proper shuffling procedure). However, I expect it will fail eventually.

Your idea of the Kopy Kat (or other similar method) would work well. After your glimpse or the first statement/question (about the lines) you should know if you are in trouble. (Although, I can imagine rare circumstances in which you won't know for a little longer. ) If you are in trouble, a good-natured laugh and a statement that "I can see that this is going to be difficult until you and I get used to each other," will get you past the failure. You could introduce the Kopy Kat (or similar item) with a statement along these lines: "Let's involve your entire body in creating the image. [Here insert discourse about about muscle memory, unity of mind and body, or whatever claptrap you think will work.] Here, after I turn my back please draw the image. Use large, exaggerated movements so that every cell in your body can "feel" and "envisision" the image. Focus not only on the image but how it feels as you draw it. Please be sure to keep the drawing out of my sight. Tell me when you have done that..."

By the way, I have let third spectators hold my wrist and "guide it" to make the drawing. This approach sometimes requires a little "shoring up." After the spectator pushes your wrist around a bit, you may have to, with their consent and approval, of course, add a few "details" to make it clearer. Yep, even in this event, they walk away believing that they have divined the drawing being thought of by the first spectator.

Part of what makes mental magic fun is dealing with the off-moments. And, you can always subtly blame and humiliate the specators for your lack of "reception." (Before the flames start: only kidding!)

I just received the Mind's Eye Deck and discovered that two cards are the same on some dimension but they should be different on that dimension. I am wondering if there are other problems like this that may cause the difficulty in shuffling the deck that others report.
Richard

Even though this string is dated, I should’ve read this before purchasing the Mind’s Eye deck. Sadly this is a brilliant idea but manufacturing quality is extremely poor. You cannot count on the basic principle. The spectators cannot properly, consistently and reliably, cut to the necessary cards, even when using all the nuances. This usually just results in complete failure. Many manufactures know how to successfully make this kind of deck. It’s sad that this dealer did not choose quality.