Setting the Influence straight...

[caravel]

I think Ironside means that it may be a bug. If it is, it proves that somehow loyalty and influence are very close if not the same thing under another name... this is entirely plausible. If the king gains two influence from marrying a princess then this proves he's getting what should have been the loyalty bonus that a general or prince would get from such a union. If the king get's an influence bonus from this, then this shows that in addressing loyalty, the bonus has addressed Influence instead. I doubt this is intentional so it must be that a king's influence stat is loyalty under another name. And once a general or prince becomes king the stat get's modified and dealt with differently.

After all there are other bugs in MTW as regards marriages. The Pope for example cannot marry directly but can be married via princesses targeting emissaries. This is an oversight by the developer and as such, technically, a bug. It is open because Emissaries are generic units and the only way to block this would have been to create "papal emissaries" that don't allow this or to hard code it (as they had done with the pope himself). Another means open to the modder is to deny the papacy emissaries and force them to rely on bishops/cardinals only. This is not a bad idea.