Landscape architect Alan Cutler made the comment during a hearing held by commissioners John Matthews and Cath Gilmour.
The hearing aimed to understand the reasons behind Meadow 3 Ltd's four applications to adapt the historic homestead and woolshed on the rural shore of Lake Hayes into luxury visitor accommodation while remedying past tree felling that the Environment Court ruled had breached land-use consent in 2007.
However, Lake Hayes architect Fred van Brandenburg, the sole opposing submitter, told commissioners that Meadow 3 should reinstate the screen that was in place, as per the consent order he agreed to in 2001.
Eight proposed buildings should be permanently screened from views by the lakeside by planting trees on mounds of earth to speed up the screening process, as it would take years for the trees to mature.
There was a gap of up to 7m between ground level and the existing tree canopy on Marshall Ave, Mr van Brandenburg said.
Mr Cutler said the proposed re-contouring, earthworks and planting would screen future buildings completely in the summer and make them very difficult to see in the winter.
Cottages would be visible from all viewpoints to the east, but that followed because the consent sought to attain scenic views from the cottages.
Arrowtown resident Don Spary submitted to commissioners that Meadow 3 had already been "punished" by the delay in development, the costs involved and the proposed mitigation measures.
Arrowtown-Lake Hayes Rd resident John Stevenson said the consent breach would be rectified and mitigated by the proposed tree reinstatement.
He said Threepwood was "a quality-looking development and everyone was looking forward to its completion."
Mr Matthews said he had "concern about the best outcome for this very sensitive piece of land" and there was a risk of "overkill as well as underkill" in the planting proposal.
He asked the various landscape architects present and Mr van Brandenburg to reflect on the balance between visual amenity and the commercial reasons to build on the property and to consider how the planting aim could be reviewed in the future, for instance, in 15 years time.
The hearing is expected to conclude this morning.
