I think it appears as:

77 Hawk House
Baynhams Drive
[Wolvercote]
OXFORD

(But the number is not a flat number, it follows the street numbers.)


Addr:interpolation on a single object is very much acceptable, and documented on the wiki, although there is no consensus.

https://wiki.openstreetmap.org/wiki/Addresses#Buildings_with_multiple_house_numbers 
> Specify the range (e.g. 10-95). Note that there is a risk of ambiguity between two meanings:
    When such a range is officially used for the entire house, this is the preferred method. In this case 10-95 is simply a label like any other. In this and other cases, house numbers officially contain a dash and are not meant to be treated as special.
    When such a range is meant to be interpreted as a list of addresses, use addr:interpolation=* (described below) to emphasise this. Some mappers will add a short "virtual" way which allows them to put addresses 10 and 95 on separate nodes as normal. Some mappers will specify the range 10-95 on a single object, where the addition of the addr:interpolation=* tag disambiguates it from the "simply a label" meaning, specifying that it is indeed to be treated as a range. Both approaches are used in practice and there is little consensus.
    Note that in some cases building or building complex has single address such as 3-5 that only looks like a housenumber range. As usual, do not convert such data blindly, without a verification.


Personally, I think it works very well and I have been using it extensively in Oxford.
It distinguishes it from other cases and it is well received for example by the main search engine on openstreetmap.org. Without the interpolation on the single object, I think it does not return addresses in the range. With it, it does. The rendering is great, and the human interpretation is also very clear: it specifies what the X-Y range means.

Mapping individual entrances certainly provides more detail, but the result is the same: a range with dash and interpolation tag on a single object.

All best.