Yes the Watchtower are devious with their wording, they use the term 'New Light' to give the impression of something refreshing, appealing, a revelation perhaps, when all it is really is a dressed up way of admitting 'yes we've f**ked up but it doesn't matter does it?'. I ask this though : if this is supposed to be Gods spirit directed organisation, why has it made so many mistakes in doctrine (old/new light) like this? To me this confirms either of two things:
1. The Holy Spirit is imperfect.
2. The Holy spirit isn't directing this JW Organisation at all.
Of course there is the possibility that the Holy Spirit doesn't exist at all but in this case for the sake of the question pondered i'm advocating its existence.