I've accompanied a number of people using IR tools on inspections - including His who have some experience with their equipment and also people who have been exclusively in the business of IR analysis for years.

Here's my take: medical imaging is a good analogy- just about anyone can detect a dramatic fracture on an X-Ray, reading a mammogram is is much dicier proposition.

Similarly, just about anyone can understand the images of overheated electrical connections and clearly-defined areas of water damage on the home pages of of the IR camera sites (after all, they have had the opportunity to choose from thousands of images) but interpreting the actual results obtained in structures - in terms of both false positives and negatives - is a much dicier proposition.

So the question you have to ask yourself is: "Is liability for the positives I'm going to miss a big enough so that it outweighs the advantages of the otherwise hidden positives I'll find?"