My personal thought is any extra layer of safety can't hurt in a mechanical mod. Even when you practice good mod/battery safety habits, shorts can and will still occur from the atomizer or within the mod itself beyond your reasonable control. Mechanical and electric components can and will fail - this is why there are fuse boxes or circuit breakers in our homes.
A regulated mod will have superior built-in protective circuitry within its processor, but a mechanical mod has none of that. Some mechanical mods have a collapsable hot spring, which when a battery reaches a specific temperature will cause the spring to melt and collapse ... breaking the electrical circuit. I'm very disappointed that some mechanical mods do not have these springs; they were the only built-in preventative measure against a hard short that a mechanical mod had.
Most mods have vent holes to allow a runaway battery to vent its gases, but that's for preventing your mod from exploding like a pipe bomb, not a preventative measure against a hard short/short circuit. So in essence, mechanical mods have NO safety features. You have to depend upon yourself to recognize the signs of a short circuit and hope that you recognize them before a battery decides to go into thermal meltdown.
I don't recall the specifics, but the various safety fuses available for mods differ in how low they will be effective as far as sub-ohms. Some are single use only, others are multiple use which reset themselves. A Kick will only be effective down to a certain ohm level. This is why I've never been an advocate for sub ohm
vaping. It's such a grey area of
vaping that IMO the risks outweigh any possible benefits. Sub ohm can push our usual IMR batteries past their limits if you don't know what you are doing. Don't even think about using a protected/unprotected ICR battery with sub ohm - that's an accident waiting to happen.
For the past year, I've pretty much stopped using mechanical mods. Over a year ago I had a protected battery vent violently in a mechanical mod - both the hot spring and the protected circuit in the battery failed to do what they were designed to do. This incident made a major impression on me as it nearly caused a fire at my workplace. At that point I made the personal decision to use primarily my regulated mods for their protective circuitry and to use either the safer IMR or hybrid batteries. I have no interest in doing sub ohm; I'm completely content to use standard resistance coils in all of my juice attachments, including my RBA's. After doing a lot of research on Li-Ion batteries, because of today's modern technology of safe chemistry batteries I've decided there is no reason to use protected ICR batteries for e-cigarette mods.
