OK accepting I hate cooking and only do the roast can you tell me please - checking online for roasting time for beef I see Jamie Oliver's recipe said to rest the meat for an hour before serving (lots of other recipes also include resting the meat). So if you are a normal person with a normal kitchen where do you rest meat for an hour without serving it stone cold?
But mamya and woofgang are correct - and with the foil and tea towel, it doesn't lose heat. Remember the meat carries on cooking in the centre 10 minutes after taking it out of the oven.....