There is only one issue I have with the method, and I haven't found a solution yet.
The varnish will randomly penetrate the polyester deeper at some points over the frame.
This causes that area to be darker at that point, leading to a blotchy look.
Once the varnish has dried, you can reach in and stretch the skin, breaking the bond between skin and frame, which removes the dark blotch. Except you can't always get all of the dark spots broken free.
More to the point, you can't reach into the ends of the boat to remove the blotches there.

The coating penetrates fabric evenly all over. The blotches are forming because the fabric is compressed where it meets the frame, and as a result the saturation of coating is deeper in those locations.
Breaking it free from the frame is debatable.
Skin being "glued" to the frame makes the entire boat very substantially stronger and stiffer.
Stronger is always good. The wooden frame is very fragile and flexible before you skin it.
Whether stiffer is good or not depends on where you paddle and personal preference.
I strongly lean to "stiffer is better" approach, but others may disagree.

Back to original question: think 3 times before you experiment with unproven coating. Even if you succeed initially, it may start failing within weeks/months.
Stick to what (many)others say worked well for them in the long run. I built 4 SOF boats with the skinboats.org coating. The oldest one is 6 years old and the coating is holding up very well.
Colean is very good, but expensive. Is there anyone who used Mr. Gentry's method successfully, and has the coating withstood the test of time? If so, it would be another cheap alternative.