My opinion of liquid smoke is that in some cases you are almost forced to use it. As in the making of Lebanon Bologna. In this case you are stuffing a 3" to 4" casing, and only smoking for about 10 to 12 hours. You will not get enough smoke penetration in that time to satutate the meat. Commercial makers of Lebanon Bologna use a secret ingredient, which is liquid smoke. They also smoke thier product for a period of 4 to 7 days at a humitity of 85 plus %. I found some of thier secrets out from my local butcher, who sells me my meat. It is hard getting these secret family recipes and knowledge form them, as this is thier livelyhood. But I do know that a certain amount of liquid smoke goes into thier product. When I first made snack stix using the Leggs brand seasoning, I added a small amount of liquid smoke, and also some brown sugar. Every one that tried them could not eat just one! I taste anylized the stix, and came up with the conclusion that if the proper amounts of liquid smoke and sugar were added to this mix, and stuffed into a large casing, that I would have a Lebanon Bologna. I tried this and I am successful with the outcome. Yes Liquid smoke ain't like the real thing, but when used within reason it can be a help. Same can be said with citric acid vs fermento. Just whatever you do, don't tell anyone. It's your special secret!
Dennis