Actually, the jets will climb with all the stuff hanging down, some with more exuberance than others but they will climb. And on heavy aircraft you had better not do anything too quickly on a Cat III approach or you may hear scraping noises on a bad day.

Also, many aircraft have flap settings with high drag for a number of reasons including having the engines will be above what used to be called 'critical rpm' or something like that, the point at which the jet engine offered almost instant response. (I remember as a kid watching the B-47s loaf around the pattern with a **drogue** chute trailing so they wouldn't have to be in idle power coming down final)( from web: Because the J47, like all early jet engines, was slow to accelerate, Boeing had devised a drogue chute that was deployed in the landing pattern and allowed you to maintain the engine at a relatively high power setting from which a go-around could easily be made. Once on the ground, the brake chute assisted the excellent anti-skid brake system to get you stopped. The brake chute had another use: if you hit front-wheels-first and bounced on landing, you could - if you knew just when to do it - deploy the brake chute and bring the airplane down to a perfect rear-wheel-first landing.)

Because many think the jet will not climb very well on a missed approach/go-around they rush. Just think, "Nose up, power up, flaps up, gear up" and it becomes a simple process.