I also think it's an appropriate site for development but can see why, say, residents of Porden Rd might be worried about being hemmed in on all three sides by tall buildings.
A quick look at the SADPD document confirms that they will be judging daylight impact in the way that seems to have been accepted for all of these sites:
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That means that a developer building on on one of these sites can overshadow neighbouring terrace-housing streets more than would be allowed normally (eg if a homeowner wants to build an extension on one of those same streets).
This issue arises in Zone-2 and 3 type locations which really were originally built as semi-suburban areas with lots of low-rise housing.
I've never really managed to find out exactly how you decide whether a site can be deemed an "inner-urban/urban location". When they say "established parameters" what do they mean exactly? In many cases it appears that you make it an inner-urban location by building your high-rise development on it.
I think it's a mis-use of that principle (which you find in BRE daylighting guides which I think refer back to various British Standards documents). I think the concept of lower standards for daylighting in inner urban sites was intended to reflect the lower expectations of people living in city centres which aren't predominantly residential and are already densely built up.
If you decide to live in an area of 2-3 storey housing then it's perhaps reasonable to have different expectations. But it turns out that now, if you are anywhere vaguely near to a local centre, you are deemed to live in an "inner urban" location and therefore no problem to reduce your levels of daylight below those previously considered acceptable