Cold smoke/white smoke/blue smoke?

For cold smoking, the idea is to either have a very small hot clean burning fire that does not heat up your smoker, or to have a hot clean burning fire somewhere else and have the smoke piped in which cools down in transit.

Smoking and bbq are two different processes. Don't try to equate "rules" from one to the other.

Heavy smoke is the goal. The smoldering fire is classic whether it be in hole in the dirt floor of an old wooden smoke house or a soldering iron in a coffee can of sawdust. My electric smokehouse uses chips in a pan over a 1000w heating element. I can't so classic cold smoking but can stay around 180 for hours to get plenty of smoke on my sausages, jerky, or whatever.

I'm thinking of getting a "Smoke Pistol" to add to my cabinet so I can cold smoke, ie. under 90 degrees.

Well, I have both a Smoke Pistol and a Smoke Daddy and use them to smoke cheeses with no problems. The smoke is white, but these are small units and I would not call the smoke thick at all. I had the same concerns as you when I first used them. I imagine if you let the smoke get really thick for a long period of time, then maybe some bad flavors would come through, but these units usually only run for a couple hours.

I don't buy the whole white is bad and blue is good concept. Take for instance, yesterday's contest. There was a down pour of rain through most of the night. Nobody could get a good thin blue smoke because of the weather. I think it has more to do with the wood you're using more than any thing. Being in apple country, stick burners use a lot of apple and other mild wood like maple here. You can run colder and be fine with the right wood. Not to mention, I have noticed that apple put's off a thicker smoke than other woods I use for some reason. But the food tastes fine. No bitterness to it at all. I agree that thin blue is the prime smoke for BBQ in most cases, but not all.