Not sure how we drifted into Offshore approaches in Scotland when the OP clearly mentioned Cambridge and Gloucester HC - perhaps you have never flown at either airfield but felt you had to make a comment?
Yes. I felt I had to make a comment because of the comment "Typically when flying an instrument approach you are in controlled airspace". Bearing in mind this is a helicopter forum, I suggest that when flying an instrument approach in a helcopter its quite likely not to be in controlled airspace - simply because of the amount of offshore IFR flying that goes on compared to that on land into airfields with CAS, and that therefore the quoted comment is misleading. The point being that a certain amount of woe and hysteria was being conjoured up for what is in fact a perfectly routine occurrence.
With regard to Gloucester (which I have flown into, though it was many years ago) if they can't even keep their radar serviceable how could they possibly manage controlled airspace - unless that airspace should exist just to allow a tiny minority to carry out intrument approaches without feeling the need to look out, at the expense of excluding or making life very difficult for many other classes of airspace users.