i have a huge coconut of a head.
For skiing i always wear a thin motorcycle balaclava, they are made out of fleece/neoprene and of very thin silky material on your skull so it doesn't interfere with your helmet...
i never had to take the padding out of my helmet to get proper fit, yet it's warm, windproof and safe....
also i have a rather large helmet (hence my big coconut) but my oakley splices fit loosely with still an inch to spare in the strap ! i wear em over the helmet like a gaper, but the way i feel is the right way....
what i don't get these days is the beanie and goggles under helmet thing, i seriously don't understand why kids wear it like that....
its so much more convenient if your goggles go over your helmet + there are better and warmer solutions than a beanie ....
i'll just leave an example of what i wear underneath my helmet ....
also, in helmets the hard foam is what protects you brainbowl, the padding is indeed for pure comfort, but wearing a beanie + goggles underneath and getting a much too big helmet and fit it way back like a gaper will completely defeat the purpose of the helmet and could possibly even be more dangerous than wearing no helmet at all ....
even tough pros can pull it off sometimes i still am not convinced it's safe/correct ....
i still want to see the first helmet manufacturer that gives me black on white that wearing goggles+beanie underneath a helmet is safe....