Why is it called Kent House?

The non-obvious thing that's supposedly still required now is the "Postal Town". By non-obvious I mean it's not obvious what the postal town would be for villages miles away from any town.

A correct Postcode is much more specific and overrides the need for a Postal Town.

The vast majority of Royal Mail addresses are analysed automatically (google "royal mail ILSM") and then this info is encoded on the special RM4SCC barcode and machine read from that point on. It drops back into human sorting once it's got to the local delivery office.

There's still the small group within Royal Mail who do their best to work out where to deliver items with incomplete, incorrect or cryptic addresses. Plenty of examples of people getting mail successfully delivered with addresses like:

    Lady with a big white dog (Sarah? The lady not the dog)
    Said she lives next to a small church
    Some village in East Suffolk with a short name

Safest thing to do is look up the address on the Royal Mail "Find a Postcode" link: https://www.royalmail.com/find-a-postcode?iid=RM0624_NAV_PER... as that gives the definitive address that they are looking for.

(Note the oddities link above demonstrates that "building name/number + postcode" is not guaranteed to be unique, although the number of duplicates is quite low.)