No. If you have two or three nearly-equally skilled and organized parties clashing they will inadvertently cause each other to stalemate. Prevent any group from building up to many fevers/highs. As soon as one person gets a high they become a primary target and quickly killed by focus fire.

"Paintrains" only really occur when there is an extreme difference in organization levels i.e. a Premade 6-8 person premade vs 2 pugs and the Premade abuses the 3rd place multiplier for Adrenalin Surges so that they get a larger number of them.

Premades as you should very well know are mostly made up of organized dps and their pocket healer(s) which a nearly impossible for non-organized groups to kill.

Most Pug matches are not determined by kills but by the side that best grabbed objectives. You can see this by the score totals at the end of matches. Often the winning team is not the one with the most points gained from kills but the one with the least points lost to deaths.