Now before you start at me, let me preface with I've been cooking with gas all my life, and as a father of two i find the setup and cleanup for gas to be much more family-friendly.
That said, I've been working the last few years to come up with a properly-tasting and properly-textured smoked result with gas, and thus far I feel, from a textured point of view, I've been doing well. Last year I had 4 fantastic racks of back rib from Costco that spent a good 3½ hours on the bbq.
I have found, though, that the smoke does not tend to last very long when using gas. I tend to use Weber chips, which are quite chunky. This weekend I soaked them for 30 minutes and the smoke itself lasted around 30 minutes before it petered out. I didn't mind much, as I was making quick ribs which only needed around 45 min with direct low heat (chamber got to around 160).
Last year, though with the slow ribs, I had to refill my smokebox 3-4 times. Granted I was using smaller chips so the possibility that they simply burned out quicker is there. But does anyone have any tips on how to make the chips last longer? My method is on a 4-burner grill, to keep the left burner on and keep the other three off and leave the meat on top of the off-three. Naturally, the smokebox needs to sit on the flame to light to begin with, but is there a chance the flame is too high (which it needs to be to get the chamber to the appropriate temp) and causing the wood simply to burn out too quickly?
Lastly, does anyone in my position have experience with using lumpwood on a gas barbecue? I'm thinking i could get a decent result if I just sit the lumpwood inside the tray of the smoke box (just so it can balance without falling under the bbq).