Note that I confined my argument to the hammer cost, not the promotions. That was deliberate, as the hammer cost is where you were incorrect.
Note that I explicitly mentioned promotions and settled Great Generals in my first post since that is immensely important in the strategic decision of where to put West Point (and even whether to build it at all).
Also, I was trying to make a point without overloading the reader with several pages of numbers. Yes, Forge, Factory, Organized Religion, Power, Stone can all make a difference in the number of hammers that would have gone to units that are instead "lost" to West Point. Do you really think that would have made a whole lot of sense for this thread?
There is a time and a place for intense number crunching. This didn't seem to be the time or the place. Was Kepler incorrect when he said that the orbits of the planets describe arcs of equal area in equal time? I'd say that was a pretty brilliant observation and that it is still extremely useful in figuring out all sorts of things today. Sure, Relativity put a (very) small kink in the observation when Einstein noticed that mass and energy both mess with distance and time. Kepler's observations are incomplete. So are Einsteins. I wouldn't call either of them "incorrect" though.
The fact that someone left a bunch of unnecessary calculations out of a basic explanation of an idea might just mean that they were trying to give a basic explanation and not that they were incorrect.
You do indeed have a point in the case where you have more GGs in the HE city than the second city. That's not universal, though, and the benefit of stacking WP with those GG XP should not be disregarded, so not so clear-cut as you imply. One of several factors that should be considered.
If I can have two Tanks with CR III or one Tank with CR III/Combat I, which do you think I want?
Seriously?
I absolutely agree that there are some cases where I will end up with WP in the Heroic Epic city. I just played a Gods of Old game as Boudica two weeks ago that was memorable because I was producing one Commando tank each turn with my Heroic Epic/West Point city and it was West Point that gave me enough XP for Commando.
That doesn't happen very often, though.
I love Commando tanks, but I was not about to shut down tank production for 9 turns just to get them. I
was willing to shut down tank production for 1 turn in order to give the Great Engineer time to build West Point.
Edit: replaced "marble" with "stone" above for West Point production multipliers.