I'll give you Justinian is bad without horses. But, I personally hardly ever don't have horses, so I wouldn't notice. The fact is that is UB works with his traits. Fast expansiion, your #1 goal is horses, which early on is manage-able on Pangea.
I just can't use the Madrassa at all. The Hippodrome was very useful during my story (see Signature) because I could stay in CAste System becuase of 5% rate. An extra ten happiness to run specialist trumps the no artist problem.
I don't play specialist, so the scientist are hampering growth, not helping as Arabia.
Justinian isn't bad without horses!
That aside, one thing that needs more emphasis with the madrassa is its culture. It will win culture wars in border cities, especially if you get it in the BCs and it doubles! +8 culture from one building is hard to match. Even creative would struggle to push that back. I rarely use the priest slots.
The whole reason I'm posting this reply, though, is that scientists are crucial even if you aren't getting the bulk of your research from specialists. Getting great people points, in some what, is very important. Let's take an example of a cottage capitol with bureaucracy. It's getting 60 commerce/turn + 50% from civic. Let's assume the slider is at 50% so 45 commerce applied to science. If you grabbed a great scientist and put an academy there, farming that scientist is worth 22.5 beakers/turn, and it will only go up.
However, it goes beyond that. Using a scientist to bulb will greatly speed your tech rate. Let's say bulbing education means getting it 10 turns sooner (pretty conservative). That means you have access to oxford 10 turns sooner. So, in addition to the base value of the beakers you bulbed, you also get 10 extra multiplier turns with oxford. Using the capitol example from above, this would be 450 "hidden" beakers. However, it STILL doesn't take into account getting to liberalism and free speech or democracy/emancipation etc faster on top of that!
Long story short, you want to make sure you're accumulating GPP no matter what else you do. Usually, one city running enough specialists will get you what you need, but you still want to run them. IMO the madrassa doesn't help beyond a regular library with this, but the extra base culture makes it a useful/average UB by itself. Your cities compete with/beat creative in terms of winning tiles! Solid.
Edit:
UU and UB totally depend on horse - no versitility at all.
UB goes obselete late game.
UB is good for raiding, but with a SOD in foreign land you need something guarding it anyway, negating it's main benefit (speed).
If your oponent has War Elephants UB is pointless.
HAHAHA! That's a good joke!
http://forums.civfanatics.com/showthread.php?t=307576
Post #9.
Granted, it was only monarch. On higher difficulties you'd have to stop before you took over the entire world with them. Then again, most games aren't just LITTERED with protective leaders either. Pick your poison. They work pretty well clean through immortal, though. As you said, you need horse, but they do JUST FINE in enemy territory

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