Distance: 1.0 km (2.5 DOC hours) - Unmarked route, hard - Moderate-hard terrain
Altitude: 910m to 1356m. Gain: 20m. Loss: 446m . Gradient: 30 deg (Moderate-hard)
Skills: Occasional scrambles (3/7) - Occasional rivers (3/6) Winter - Iceaxe/crampons, avalanche risk (5/7)

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

Primary, unmapped (2/5)
Route not on maps, but is principal access to hut or along range / catchment

Moderate-hard (difficulty: 4/5)
Continuous moderate climbs

Moderate-hard (difficulty: 4/5)
Tall, walkable scrub / large rocks, occasional waterfalls or gorges in rivers

Occasional scrambles (difficulty: 3/7)
Tramp with some scrambles and exposure to falls

Occasional rivers (difficulty: 3/6)
Occasional rivers - impassible after heavy rain

Iceaxe/crampons, avalanche risk (difficulty: 5/7)
Ice axe and crampons required, crosses avalanche paths

Coming down - the turn off is not marked, descend the open tussock spur/face to the scrub then aim to drop into the side stream no more than 200m up from Sir Robert Creek, steep eroding scree makes access very difficult any higher up.

Note: Described in the reverse direction to your journey

Down Sir Robert creek to the small side stream coming from the TL down an open eroding staircase. Up this side stream a short distance before breaking up the bank or up a small trickle into the scrub.
Staying in the side stream is a mistake.