It reads to me like he meant it in a river-being-water sense. AKA you may be MrRipley now as yesterday, but the atoms that make you today aren't yesterday's.
The turnover thing isn't so much something he exploits, at the (unfortunate) expense of players, but more of an inevitability. It's something you can't work around - every player (save a small minority) will eventually burn out or otherwise move on. Not building your business model around it means you go extinct sooner or later.
I'm naturally not trying to tell Hitech how to run his company but in my opinnion an online game should be treated like an ecosystem. Each player has his reasons for subscribing and playing and their actions affect the fun of others not just themselves. If there are disruptive elements on the arena causing the fun element to suffer or disappear, like in an ecosystem they're at first compensated but if let loose, will damage it permanently.
To me, overly massive hordes are like locust storms that eat away the nourishment of the game. The game changes from a fun challenge to an act of futility and negative returns. One may think well it's just a field who cares - but as one sees the situation progress field by field it's clear that if nobody stops the mobbing mentality, the fields are soon reduced to the stage where the country ends up 'in the bucket' and vulched till arena resets.
I think changes to the game were made that made the situation before the 'war ends' less insane by allowing more fields to be left before reset and were absolutely brilliant. Back in the days when IIRC two fields were left in the end, gameplay just went down the toilet for the last hour or two. If those two hours happen to be your only available gametime you might aswell not log on.
So, as long as things have some sort of a balance the garden of players can flourish and grow. Again, IMHO.
Attrition could be used as an incentive to not horde up - instead of the ENY that follows directly player numbers, what if ENY would change dynamically so that the more low ENY planes you lose in a horde combined with number superiority, the less would be available for the next one. Meaning at first you have P51D etc. at will, make stupid horde runs and get 30 of them shot down in a short manner, you no longer can use them for some time. That would possibly make two things happen: A true positive return for defending succesfully as the enemy would be visibly hurt, even weakened, from deaths and on the other hand incentive for the attacking party to try and survive in their planes instead of blindly lawndarting in search of instant returns.
