NPPF - what is poor design?

The NPPF says at para 64 that 'Permission should be refused for development of poor design that fails to take the opportunities available for improving the character and quality of an area and the way it functions.' Good stuff.

The consequences of new policy documents take a while to become apparent, and it may be a year or so until we find out which bits of wording are the 'sites of contention' in this document, but this is likely to be one of them.  Previous policies did not go this far.  Paul Finch pointed out in a recent article that the wording in the draft referred to 'obviously poor design' - and that the (welcome) loss of the qualifier in the final version might come to be seen as significant. (No doubt it will be argued that the second half of the sentence qualifies or waters down the first half - but the second half ('fails to take opportunities...') is in fact simply an inevitable attribute of poor design.)

What are we to make, for example, of the average product of the average housebuilder?  Generally speaking, it represents  'poor design' in all sort of ways - even without considering what it looks like, which compounds the offence in most cases.  Will all this stuff - and the (let's say) 50% of all new development, as seen (let's say) from your window during a long train journey -  that represents 'poor design' - be turned down by planning authorities now?

And if not, why not?