Hi Tom, I am using a similar product from Germany, which is famous for that. You will be surprised about the difference such products make for your leather. I have restored my 24 years old E32 seats, the leather had cracks, I used liquid leather to fill the cracks, let is dry, applied again and then used the colour stuff. Even completely torn leather I repaired, I took the leather off the seat, glued from the backside with leather glue a piece of leather, and then applied again liquid leather to fill the crack and then used the colour.
Leatherique calls the liquid leather crack filler.
http://www.leatherique.com/do_it_you...r_application/
Lots of instructions in here Home Page | Leatherique Restoration Products
In Germany most famous brand is Willkommen | Lederzentrum - Spezialist für Lederpflege, Lederreparatur, Beratung
see the videos, language is of course German, but that does not matter, especially the one with Fluessigleder = liquid leather = crack filler
Die Reparatur von Farbschäden bei Autoledern | Lederzentrum - Spezialist für Lederpflege, Lederreparatur, Beratung
Risse und Löcher in Glattleder mit Flüssigleder reparieren | Lederzentrum - Spezialist für Lederpflege, Lederreparatur, Beratung