I started a similar thread the other night,
http://www.smokingmeatforums.com/t/233841/so-what-burns-longer-wood-or-charcoal#post_1458730
I'm using a stick burner and used charcoal, as little as possible, oak splits, for heat, and apple for flavor. I did an 18hr smoke this weekend, 40ish lbs of meat, not all at once! I used 18lbs of Kinsford blue, 30lbs of oak splits and 15lbs of Apple splits.
I'll say you can do it with splits, but it requires more effort than charcoal. I have a Brinkmann trailmaster offset, it's not efficient at all! I can easily go through 18lbs of charcoal of a simple smoke! I can get a LOT of oak at the prices for charcoal!
But, hickory and apple are hard to find, read expensive, around here!
I don't get the "charcoal for flavor"? I use oak when grilling steaks for the flavor, not charcoal? I use oak for heat when smoking, then add fruit wood, and/or hickory for flavor. I just don't see where charcoal imparts that much flavor?