Distance: 3.6 km (4.0 DOC hours) - Unmarked route, hard - Hard terrain
Altitude: 192m to 1440m. Gain: 1253m. Loss: 13m . Gradient: 21 deg (Steep)
Skills: Alpine weather (2/7) - Streams (2/6) Winter - Snow/ice underfoot (2/7)

Unmarked route, hard (8/9)
Unmarked route, no clear geographic features to follow

minor (5/5)
A viable route, not widely used

Steep (difficulty: 5/5)
Steep climbs of >1000m

Hard (difficulty: 5/5)
Thick scrub-bash / continuous river boulders, waterfalls, or gorges

Alpine weather (difficulty: 2/7)
Tramp on open tops, exposed to alpine weather

Streams (difficulty: 2/6)
Small streams, danger only in extreme weather

Snow/ice underfoot (difficulty: 2/7)
Snow/ice likely on track

possibility of there being snow on the tops in winter

Personally, I would never try this, it's steep, dense bush that would be very very difficult to push your way up through.

Note: Described in the reverse direction to your journey

Relatively easy going from pt 1453 to the bush line, once in the bush try to stay away from the creeks, they have steep sides and make travel difficult. Overall travel is very difficult through the bush, it is pretty dense and doesn't ease up. At 500 mt elevation contour, there are some small cliffs, you can get bluffed out but we managed to scramble down them, be confident in your ability before going somewhere you can't get out from. Once past these it's more dense bush all the way to the boat harbour, then just follow the shore around to the hut