Nick, nice article. I gotta say, when I get around to putting these articles on my web page, they do bring in “Eyes” to my Site. 
This phrase is old and out of place for homes…:
“Inspectors may … They may also recommend that clients use commercially available combustion-enhancing, acid-neutralizing fuel additives to prevent damage caused to vents from sulfuric acid.”
How are homeowners going to add these products to their furnace/boiler/water heater oil/gas fire chambers???
See: http://www.atlcombustion.com/comate/
I know the owner of this company that produces and sells combustion additives… but only to large commercial boilers/incinerators. (have done commercial and home inspections for he and his son). He started selling his product to those using wood heating systems but could not convince well trained WETT techinicians and wood stove vendors that it had any effect…nothing was ever proven!!
See the sections on how the product works in large operations.