For what it is worth, before I retired from dinghies in favour of the yacht I regularly sailed my successive GP14s single-handed, but I was prepared to reef as needed, although I concede that this was primarily cruising rather than racing.
My home club have an annual single-handed trophy race, specifically for two-handed boats sailed single-handed.
I am not aware that the Class Association have ever considered a specific conversion to create a single-handed class. I may be wrong, but I see no reason why the standard class boat cannot be sailed – and indeed raced – single-handed, provided that any racing is on an equitable basis. The latter might be a matter of establishing an appropriate Portsmouth Yardstick for the boat when sailed single-handed; and the key to doing that is the provision of race results … …
However it is an interesting proposal; let’s see what others think
Oliver