M0nica: Unless I am mistaken, the original question in this thread was about the IHT on a gift before death which is what I have tried to address. For gifts before death, liability to IHT falls on those who received those gifts. However, it is my understanding that, if an appropriate clause is included in the will, the estate can pay the IHT due upon those gifts during life. It seems a sensible way for a person giving money away before death to ensure that the person receiving the gift does not face a tax bill in future.
I notice that the new IHT relief on own homes tapers away to nothing on large estates over £2m. So, for large estates, the IHT exemption remains at £325,000 per person.
I think the new relief was introduced, in part, to protect children living in the family home from having to sell their home to pay IHT when a parent dies. The average house price in the SE is over £300K and, in London, almost £500K so this situation, with just a single £325,000 exemption, could arise.