Must admit have read this thread develop over time - I really liked your first rule of 15's - as an engineer KISS often applies to good effect - plus it is short punchy and straight to the point and so easy to remember at my age!
I can sleep easier now!
FTP900 +Sightron S111 10-50 x 55
AA Pro Target in FWB FP70 stock + MTC Mamba lite
Daystate Airwolf + Bushnell Elite 6500
" life is about the memories we hold and not the things that we own"