SI 2007/241 (
http://www.opsi.gov.uk/si/si2007/20070274.htm) which makes the amendments is clearly talking about modifying the visibility rules for helicopters. It is only the amendment to article 155 giving the definition of "with the surface in sight" that modifies the visibility rules for other aircraft. As the amendment to article 155 is to the notes for interpretation of the act, and this has been changed as the result of substantive change to only those articles of the act relating to helicopters as set out in the SI, it could be argued that the amendment to the interpretation is also only specific to the interpretation of the act as regards to helicopters and not other aircraft. So taking into account the SI which amended the interpretation, the interpretation is open to interpretation.
I think I need to go lie down somewhere dark...
(now maybe a real lawyer can tell us what it really means)