I am not all sure a #11 pinched to allow it to remain on a cone would lead to a chain fire. If that’s ones own experience on a particular revolver then by all means don’t do it. I’ve gone thru numerous thousands of
#11caps, Remingtons and CC’s on revolvers from the 1862 Police, the Navies, the Armies, a Walker, ROA’s Rogers and Spencers, an G and G and a Spiller Burr and a revolving carbine.
I did experience a chain fire just last week on the Remington Revolving Carbine. The #11 on one of the cones fell off, I hadn’t pinched it.
But that’s just me and my guns.