[Shangrila00]

There's definitely some preferential targetting going on. Fire archers does target javelins in an army with only melee troops, but will target bow/crossbows over javelins even if the latter is closer. I feel kind of stupid since that was obvious with the way that lots of indy armies mix archers with javelin armed light infantry. So you definitely can't decoy fire archers with javelins. Don't know about slingers, though it doesn't seem worth looking into seeing as how slingers are just as squishy and no cheaper than indy shortbows.