I was planning to use flexible rafter roll to create ventilation channels to promote air circulation from the eaves to over the top of the loft insulation rolls in my cold attic space. However the Manthrope fitting instructions warn that the loft insulation should not be pushed tightly into the gap between the wall plate and rafter roll. I assume there is risk that the loft insulation will push up against the roof breather membrane and obstruct any water dribbles flowing down the gradient of the