After 14 years with my Cook Shack I started getting a bittter taste to my bark. I know that means creosote. I hadn't varied my smoking technique at all. I hadn't cleaned it in 14 years.
I finally broke down for my first cleaning. I used food safe grill cleaner and a power drill with brush attachments and a little bit of water. I didn't get crazy but probably knocked off 70% of the crud. There was pretty caked up grease in the corners. Made me cringe. I don't care what they say about hot temps killing bacteria-LOL.. I even used a little bit of dish soap and water.
i seasoned for 3 hours(which also served to evaporate any dampness). Viola! The bitterness was out of my bark on my next smoke.
I'm not a fan of frequent cleaning. i think of it like a cast iron pan. But every once in awhile a guys gotta do what a guys gotta do...