Excellent question, thanks for asking!
Encap-Punch is not a so called "film former". As I see it, a "film former" is an excuse made for a "wannabe encap product", when the product does not crystallize like it should. Without proper crystallization there's no vehicle for actual soil suspension and soil recovery to take place. After all, the soil in the carpet is not going to magically jump out of the carpet and into the vacuum cleaner. LOL
Encap-Punch is a true crystallizing encap product. One of the things that helps it to shine as a bonnet cleaner is due to its "low foaming" nature. Having a light layer of foam is not as effective when it comes to bonnet cleaning. A fine layer of foam can create a barrier between the bonnet and the carpet surface. With bonnet cleaning, we want the soil to be absorbed directly into the bonnet as efficiently as possible. Not having a layer of bubbles present enables a low-foaming product like Encap-Punch to draw soil straight into the bonnet more efficiently.
When you perform bonnet cleaning with a true encap detergent (like Encap-Punch) you're actually utilizing two methods of cleaning... (1) Absorption, and (2) Encapsulation. Drawing soil out of the carpet and into the bonnet can be a very effective low moisture maitnenace method. And when you add good encapsulation to the mix, you're improving the cleaning that much further. Encap-Punch will also help to resist resoling because of its brittle polymeric nature and its built in protector. And since Encap-Punch has got the fire power of a "pre-spray" it also has enough muscle to plow through dirty carpet.
I hope this brief overview helped to answer your question.