Wouldn't be as effective. The Rune Beetle wouldn't have as high of RC uptime due to using Bleed Attack as well (same problem Cu has, one of the reasons Triton is better). Plus it wouldn't be as tanky, Rune Beetles don't have Healing like Tritons or Cus do.I'd like to try the template above with a rune beetle trained in Discord + RC.
RC and CB do stack though, so if a Triton hits a 80 Energy Resist boss with CB, it'll drop to 40 Energy Resist, and if a Beetle then hits the boss with RC as well, it'll drop even further to 20 Energy Resist.