Reporting back regarding the effectiveness of Renovo.
To be honest I didn’t use the warm air trick, I simply followed the instructions provided on the bottle of Renovo which was wash the surface with warm water, dry, then use small amounts of Renovo in small circles, allow to dry then polish it off.
After doing each screen on both sides twice I can honestly say the cloudiness has gone, that’s as far as I can tell but it doesn’t seem to remove deeper scratches with the first few goes although that’s not to say that with more perseverance it wouldn’t produce more fruitful results?
Hope this helps to throw a little light on the subject 😃