To get things clear, the militaristic trait does not directly increase the probability of an MGL. It DOES increase the probability of promotions for conscripts, regulars, and veterans. First off, you want to fight with veterans... not regulars (regular units have their uses as scouts or maybe as military police, but little else). Second if you can whack some barbies with your veterans, do so. The probability of a promotion for a veteran vs. barbies doesn't come as high as fighting an AI, but it does exist and below Deity you have combat bonuses vs. barbies. Third, as TheOverseer714 pointed out, redline (1/2, 1/3, 1/4, 1/3, 1/5 status) units with bombardment BEFORE attacking with an elite. On top of that, until you get a good feel for special situations where weakened elites can win handily, ONLY attack with 5/5 elites. Also, try to attack the weakest unit defensively around... warriors instead of spears or longbows instead of swords to increase the number of battles that elites win, and to keep your elites as healthy as possible. Generally, don't attack a city with an elite first, even if you've redlined all defensive units in a city, as an artillery unit or a longbow or archer (or guerilla for that matter) might get a defensive shot at you before you attack (as TheOverseer714 pointed out). Fourth, generally use horse units (I suppose mechanized units also), instead of swords (save for the Gallic swordsman) and maces, for fighting battles to promote to elite and then to fight for an MGL. Horse units have a probability of retreating which maces, swords, and other infantry-class units do not. Lastly, practice patience when farming for MGLs.