Originally Posted by Fat Woody
Yes, they should, but if you've ever had a split roll off your coal bed, or got distracted from babysitting your cooker, or any of a thousand other real-world things (chit) happens, it's good to have a backup plan! A chimney of charcoal will get you back in the game (and back to burning wood) in a hurry.
I totally see where you are coming from about how you can get pulled away from the fire management and I agree with Buttburner that there's nothing wrong with tossing in a handful of lump to add to the coal bed, after all lump is just carbonized wood but dumping "chimneys" of charcoal into an offset is risky. Charcoal tends to ignite quickly (and all at once) and the result is usually spikes in temperature which leads to choking down on the intake to control the heat. If you choke down too much on a fire that has wood in it, it will smolder rather than combust and then it's goodbye thin blue and hello creosote and bitter food not to mention the toll that wildly fluctuating temperatures will take on your finished product. I always keep some kindling near by in case I need to jumpstart the fire but as soon as the kindling is burning, I'm putting a split on top of it to begin rebuilding the coal bed. My dampers are wide open and with good airflow it doesn't take long at all for the fire to catch back up, giving good heat and insuring clean smoke. Contrary to popular opinion, offsets are wood burners, NOT charcoal cookers! Staying with wood only will give you a much more consistent and manageable fire in a stick burner and consistency equates to killer Q.