One Hoop: Thanks for bumping this article to where i could see it! I'm glad to find out about this unexpected upside to explorers.
As for Conquistadors: While I wouldn't want to write a strategy section on it yet, I'm thinking Conquistadors and their movement bonus might well make them lethally effective in a medival Jungle Warfare campaign. I'm about to find out. I'll post a save of the game I'm playing with the Spanish momentarily. You'll see the southern, jungle-choked area of my home continent has recently become infested with some unwelcome intruders as of late; Japanese, Byanztine, and Sumerian cities (The Japanese city is close to a source of precious iron which seems rare in this world, and one byzantine city is holding holding 4 gems in it's sphere of influence; I already have 2 gem colonies linked up and a source of iron, but I'm greedy. My attempts to rush culture in my nearby cities and flip 'em is not working, so I'm going to soon grab them the old fashioned way. The land is, being jungle naturally very underdeveloped and lacking in roads, so I'm thinking I'll send my Conquistadors down there to secure the goods.)
So yeah, not ready to put a strategy article out there, and this does seem so far to be a rather narrow window of opportunity (jungle welfare against an enemy of inferior resources/technology), we'll see how they do.
EDIT: here ya go. You'll see a lot of my Conquistador Jungle Warriors to be are out of position right now, but you'll get an idea for what part of the land I'm talking about and what I'm planning.