Of course, those of us who love our speed would like to have full-fat FTTP, but I completely get why most areas won't be seeing it for a long time.
Alongside the excellent technical discussion so far in this thread, you have to consider the economic and legal issues around FTTDP v FTTP.
To a rough approximation, FTTDP and FTTP involve running the fibre network approximately as deep, so to that point the costs are the same. (There will, of course, be some variance depending on the size of the DP compared to the typical 8 or 12 way split of an FTTP beam splitter).
The question is what option is cheaper from that point.
FTTP involves running a fibre into the premises, but does not involve installing expensive active equipment at the DP, there's no need to get power to the DP, and the installation part of FTTP is pretty much a 'once and for all' deal so far as future network upgrades go. Openreach have already run co-existence tests with prototype 10GPON over their FTTP infrastructure in Cornwall - all they had to do was fit 10GPON equipment at the subscriber and head-end, whilst GPON users on the same split remained unaffected.
FTTDP uses the existing metallic pair from the DP, but does involve installing expensive active equipment at the DP which needs power (which might be back-fed from the end-users). There is fibre at the DP which could be converted into 'full' FTTP later, but if there were future upgrades to the FTTDP technology, you'd have to change the equipment at the DP.
It may well be that both options are rolled out as fibre moves ever deeper into the network.
FTTDP is particularly attractive for multiple-occupier buildings such as flats, because the cables from the DP are typically short, and there's no need to get freeholder permission to run a fibre through the building to each served property.
For houses, it might turn out to be more cost-effective (especially over the medium to long term) to skip FTTDP and go straight to FTTP.
Obviously the economics of both FTTDP and FTTP will change over time as installation techniques are refined and the equipment gets cheaper.
At the moment, it's a hypothetical comparison as commercial FTTDP equipment is some way off and the focus for the next 5 years or so is on the BDUK project targets. It is possible that FTTDP will prove useful in the later stages of the BDUK project. I'm less sure we will see near-term widespread use of FTTDP as a speed enhancement product for those whose connections already qualify as superfast.