I have no idea how good or bad it is will try and find more information and keep you posted .
Coming soon to a roof near you . This is new try and be ready .
Asphalt shingle Coating
Techni-Seal Elastomeric Roof Coating is an economical solution which spares the replacement of the roofing material. It stops the deterioration of shingles or membranes by fixing their granules. Good-looking, it can change the colour of the existing roofing in one coat.
Roy Cooke sr Royshomeinspection.com