Plod -
I have not seen a published approach where a non-precision approach, depicted with CDFA, has a Decision Altitude (DA). I would expect to see a published Minimum Descent Altitude (MDA) as it is non-precision.
As far as I am aware, the legal bit is clear, at a DA(Precision Approaches) a decision is required, and if a go-around is the decision then you will descend below that DA quite legally during the process. The MDA(Non-precision approaches) is the MDA, and is a not-below altitude unless you have the required references.
There are exceptions to these under certain circumstances, but in general, this is the legal situation as I see it.
HH