I have done water damage repair on several campers. Just a small amount of water will ruin a wall or roof.
My plan is to touch up the dicor once. I do not layer and layer it on a spot, after a spot has been touched up then the 2nd time I will scrape it off and start from bare. It scrapes off so easy with a scraper.
Being paranoid about water damage is good. Water means death and is why RV's typically die. Water damage is the majority of problems in RVs.
A friend kept layering on silicone and it looked like an ice cave formation, but still leaked. Silicone is a disaster as it is hard to scrape off and layering it on just made the leaks more of a labryrinth
I have used Eterna bound. If you over-lap the tape then that area will leak. Use Dicore where it overlaps as the tape will never fill in the tiny right angles the tape makes on its edges. Use dicore everywhere the tape meets or overlaps, then it will work and likely not leak. Dicor is easy because it can just be scrapped off and redone, where Tape makes a mess to redo.
Tape has its uses.