A few cases where my ferrule got stuck...
a) 30-ish pound tidewater chinook on an 8wt single hander landed, released - couldn't get the rod apart before work so I had to drive with it partially out the window
b) replacement half after rod breakage never fit right, any use without a separating agent on this rod is risky
c) used the 9wt striper rod without ferrule treatment for a long time and one day it got stuck bigtime
Your results may vary