helps promote a more uniform flame travel. IE: more stable, thus minimizing the chance of detonation.
thats the only thing proven to work. V-grooves~U-grooves~slit ground electrodes~etc are all marketing gimmics.
Platnium~Uridium~Titanium~etc tip plugs DO NOT promote a better spark, but are super hard and VERY wear resistant.
hence the "go 60k without changing them" statements. Also there 3,5,7 times more $$$ then conventional plugs.
now, i buy my CHAMPION J12YC for $3/pair, and change em once every couple of years regaurdless of milage, and
i also inspect them twice a year, just to make sure there are ZERO problems. If one plans on keeping there
plugs in there small/big block MoPar for more then say 8000 miles, you gotta be