Access to Blue Lake is delicate. In terms of summer climbing there has been a few encounters with NPWS staff and enthusiastic conservationists who have concerns about people walking accross the fragile ground between the hardened walking trail and the cliffs. To avoid this try and go midweek and avoid long weekends when encounters with parkies are more likely and tourists might follow you off the track.
Given there are genuine access issues I'd limit any drytooling- whether or not it actually impacts on the rock.