This is not true of modern fan controlled heat-modulating boilers. The most modern boilers available in Germany (i.e. manufactured within about the last ten years) achieve effiencies of typically 103% (for oil) to 106% (for gas), because of the way the heat content of the fuel is defined. They achieve this by recovering the condensation energy out of the water vapour which condenses in the chimney. The exhaust gas is so cool (<50°C) that you can put your hand on the exhaust without getting burnt. A typical boiler for a modern family home of, say, 120 qm will have a rating of 12 - 13 kW as opposed to over 20 kW a few years ago (30% or more of which, disappeared up the chimney).
Current building regulations require a normal family home to use no more than 30 kWh/qm/year - equivalent to 3 litres of oil. This means your typical 120qm home will require 360 litres of oil per year. Before 1995, when they started tightening up the requirements (yes for Kyoto, amongst other things), a typical house would have used between 140 and 200 kWh/qm/y. So your typical house would have required between approx 1700 and 2400 litres of oil / year. Since oil isn't getting any cheaper, this is not just leading to decreasing CO2 output, it's also saving hard cash.
Oh, by the way, if you have an older house and you decide to renovate it, or build on to it, not only do you have to meet the current standards (which is pretty obvious really) but if the area involved is more than 20% of the original living area of the house, the whole house has to be brought up to the new standard - that can get VERY expensive indeed - to the point where I'm not sure that it might not be counter-productive!
and better still individual TRV's on each rad
is considered self-evident over here. Many people, including myself, use the kind where you can program the times where you want the full heat, for example in the bathroom for an hour or so in the morning (a different hour at weekends, of course) and then slightly cooler for the rest of the time. This is in addition to the normal overall boiler temperature reduction at night.