" I try never to go below 18 AWG (stranded) because ........ "

Isn't this a GREAT country?  We can do it the way we want to.  I used 26
gage MIL spec wire exclusively for low current wiring.  Increased the size
only where necessary for current rating or voltage drop considerations.
Have been flying since 1994 and have had NO problems with wire breakage.  In
addition to weight savings, the wire bundles are smaller and easier to
manage.