But it means "fighting against infidels by sword" and that meaning was vastly prevalent in the CK timeframe. "Crusade" today also doesnt always mean "armed struggle for the cross" .... should we consider dropping the "C" from the "CK"?
You're both right and wrong in different ways. 'Jihad' literally means 'struggle' and although sometimes it does imply armed struggle, sometimes it certainly does not. I'm not going to go into a full listing of all the uses of 'jihad' theologically or politically but just as an illustration, the root J-H-D (look up 'Semitic roots') is also used for terms like 'ijtihad', which refers to the independent use of reason, particularly in an Islamic juridical context. This point is as true in a medieval Islamic context as in a modern one.
I would also observe that contemporary Christians did not refer to their religious military adventures as 'crusades'. That was a label applied later on in the Renaissance; they were called many things at various times, but the First Crusade for instance was referred to as an 'iter' or 'peregrinatio' ('journey' or 'pilgrimage' respectively, in Latin).
In any case, I agree that it isn't really accurate to make jihad a mirror of the crusade mechanic (which, agreed, is itself more than a bit ahistorical mechanically); within the game's timeframe (i.e. well after the end of aggressive Umayyad expansion) none of the wars initiated by Islamic rulers against non-Muslims resembled the monumental outpourings of Western Christendom onto the Asian continent. The recapture of Jerusalem was not an anti-crusade that united the Muslim world in opposition to Latin Catholics, let alone eastern Christians, and it certainly wasn't driven by a caliphal fatwa.
It is also important to note that the medieval ulama had an extraordinarily legalistic view of the expansion of Islamic authority and diplomatic relations with non-Muslim domains which had more nuance and gradiation than the neoconservative charicature and modern fundamentalist misapprehension of there being a simple polarity between Dar al-Harb / Dar al-Salam (i.e. enemy of Islam / submitted to Islam).
Suffice to say without a complete overhaul of what Islamic rulers might consider a casus belli compared to feudal Christendom I would agree that it would make sense to dispense altogether with the jihad mechanic and make Muslim 'holy wars' more regional affairs. It should also be more difficult to just collect territory as a small Muslim domain, essentially because folding foreign people of a different religion into your realm takes a lot of effort and manpower. But I think that's also an argument for anti-blobbing mechanics generally - Basil II would understand...
