An update to the thread - as might be expected, the Advertising Standards Authority (ASA) has agreed with GWPF that the offshore wind advertising campaign conducted by Greenpeace in association with other groups mentioned earlier in the thread was misleading:
However it only amounts to a minor scolding, Greenpeace has got away with just giving an assurance to the ASA that it will not use the disputed claim again in any future advertising campaigns.
Only the Daily Mail seems to have publicised the story that the advertising campaign was misleading, so it is possible that any politicians and civil servants who were actually influenced by the campaign over the past few months will not be aware that the campaign was misleading, as Green-leaning people don't tend to read the Daily Mail.
I would argue that the BBC should not employ any actors, like Peter Capaldi and Emma Thompson in this case, who have been associated with misleading advertising campaigns. The BBC has always taken the noble position of avoiding being funded by advertising, so it would be consistent for them not to employ people connected with misleading advertising.