i dont think teh imrc is acting up in your issue. ive always feathered the clutch in on my focus or it felt like it would die at teh light. with or without a tune. however i'm used to a big heavy pickup clutch.
FYI imrc should open at about 4500 or higher if i recall.
ald it always helps to at least run it all the way up close to redline once a day. the svt is a fickle little thing, and it'll let you know immediatley if something is off.
your car will never be like my car, after all you have common sense......