Ok, I have to cry foul about the designation of the Spiculom as an IR missile with IR being said to equal Image Recognition. IR = Infrared. Always has. Always will. Calling an IR homer a heat seeker, as in the case of the Javelin is merely dumbing things down for the masses. Image recogniton for homing is a form of aspect seeking, in this case, visual aspect, as opposed to radar aspect for radar homers.
I regret that this particular item grates on your nerves. You are correct about the initials IR. However, those are the initials that Chris Roberts chose for his Image Recognition missile, and since what we are doing is within the fictional universe he has created, we are obliged to follow the way he has done things.
Belive me, if we decided to call it something more techincally correct, the backlash would not be worth the accuracy!

I hope you can just grit your teeth and bear it about this particular point. I know you're right, this is just the way we have to do it for the sake of the fictional universe we are writing for.
It is, after all, probably more pulp fiction than science fiction. Hence, little inaccuracies are typically winked at, so to speak.
But, good call nonetheless.