Potential weakness of bezel-end twisties?

I've read of some having problems with their Arc-P's not working. The old bit of aluminum in the bottom of the tube fix. My first CMG I.U. is having not serious issues really, but it blinks on and off at a point where it didn't used to. Still works, but it occasionally blinks. Is the front-end twisty on some lights causing a problem if tightened too hard? I noticed the circuit bord on my I.U. has a small space around it now, like it's been pushed up a bit. Maybe by cranking it too tight against the battery? Is this an inherent potential problem with this type of light? Any particularly bad culprits susceptible to this? Thoughts? Ideas? Maybe tail cap twisties not so bad? Though they seem to have their issues as well.

sure seems AAA alk cells leak more than any other type cells.

don't know if this is due to twisting action, camming against cell or AAA's just leak more.

I'm inclind to believe AAA alk cells leak more. I've had mulitple alk AAA cells leak. since I'm the only one that tighten ARC AAA head. I can state this ARC AAA was not overly tightened and AAA alk still leaked.

leaking alk AAA cells are responsible for most of the ARC AAA in field failures I've seen. that's why new ARC AAA went to a stainless ground post design.

fyi, if you do get a leaky AAA in your ARC AAA. send it back to ARC. Peter just posted they would take care of leaking light problems. even though ARC is not responsible for damage caused by leaks.