I am apparently older than everyone in this thread so far and it does not worry me a bit. Apart from occasionally suffering in other people's beds, from birth I have always slept under a duvet/downie (or whatever it might be called), and always accompanied by central heating (sometimes airconditioning) except when away from home (temporary or permanent). Yes, always containing down (swan, goose, duck - rarely eider), not feather at all, and therefore very light, I/we find the synthetic ones very disappointing. Always a single and my wife (and girlfriends before that) has her own single - no adverse affect on love life, contrary to popular myth. They have all been the same grade/weight, I have no idea what a tog is and I don't know who really does does, so far as I can tell - apparently a very loose term and not really relevant to the insulating qualities which after all is what matters. I have slept under mine on a work assignment (we take them with us on such occasions) where the overnight temperature in the room dropped to freezing - I only found out when I got out of bed ! Our sons will not consider anything else and sometimes insisted on taking theirs with them when visiting friends (more comfortable than sleeping bags). If it is warm in the room then you simply dangle a leg or arm - until it passes the point to where a simple sheet will do (not applicable for those who always sleep completely covered, including the face), but please no blanket - the two slide around independently and being trapped under tucked bedding is for me intolerable.