Whether its Gel coat or acrylic paint is immaterial, what I was shown was numerous pin holes through the outer surface that would allow water to penetrate through to the composite beneath. Now allow that trapped water to freeze and just watch what happens to the airframe. I doubt that the Tutor is limited to operations in positive OAT only.
I'm far from being metalcentric, in fact I truly believe that an aircraft isn't an aircraft if you can't poke your finger through the fabric.