Well, games could be played even without engines just by following previously played games. We’re far from computer chess when we do that. 
In the current Computer Pool settings, the winner of the Computer Pool is the one that disconnected the less, lost on time the less, faced weaker engines more often than others and had a good (recent) opening book. Nothing in that really showed the best engine. The fact that position #1, #2 and #3 are still around 2350 rating or less (not counting the .5 point per win given which should be removed imo) just shows that there is parity and mostly luck is determining the winner. Not luck at winning, but luck in who you are facing more often, and (bad)luck that influences your opponents and favors you in the outcome of games.
Yes there are some very good computer setups in the top 5, but some are fluctuating too much (except 2, Enginemaster and RayJr). My computer has beaten every engines out there except Enginemaster, and I run on old hardware (2010, 2011 and 2012) that I OC’d a little to give me some more kn/s. Enginemaster as lost only 11 games for 165 wins (as of this writing) and is only rated 2358, while you CoolNite (for example) are rated 2344 with 35 losses for 155 wins (as of this writing also), and you both have almost the same number of games played (near 620 games). This just shows that luck of opponents really determine the rating and not the strength of the engine. RayJr on its 818 games has lost less (32) and win more (177) but is rated somewhat lower then you both. I find that is not really representative of the strength.
If I take the Nunn’s Positions to establish the Computer Pool, all engines would have to complete 20 games as white and black against each other opponents in the pool. To be entitled to win the pool, you have to compete at least vs 10 (or more/or less) other engines AND complete the set (of 20 games white/black). Once you have completed your 10 engine sets (that 10 opponents x 20 games = 200 games), you can increase (or maybe lower) your score (win would give 3 points, draw = 1, and lost = 0 - no engine rating!) by playing other engines that still have to complete theirs. Some bonus could be given to these engine because they help other engines complete their minimum set. This is just a suggestion of how it could be done. Disconnection would not count as lost as the game with that particular Nunn’s Position would have to be played again between the same two engines so it can count.
Anyway, congrats to the winners of this month!