Tin foil or no tin foil?

"I built a home made smoker last year and used it probably 10-12 times with varied results. I have been trying to concentrate on making the perfect pulled pork. To be honest of all the times I tried I was only really happy with the results on 1 occasion.

I will try to describe the process I use before I get to my real question. I have a homemade smoker with an offset firebox. I generally get the fire going with some lump charcoal and then keep it going with oak, cherry or apple woods. I try to keep it low and slow 180 to 220 degrees for about 10 hours.

Someone told a friend of mine to wrap the pork in tin foil approxiamatly half way throung cookimg amd then raise the temp of the smoker slightly but no higher than 250 degrees. It worked well for me on this one ocassion the meat fell apart and tasted delicous. What methods do you use? DOes anyone strongly fopr or against using foil? Sorry so long but thanks for the help."