If you consistantly
don't use the name at all, then nothing will be done to the file that can't be done using the handle alone (e.g. open a secondary data stream). In that case, Copying the file via the handle should work properly, too.
However, File::Copy might not copy security attributes or other things if given handle only; that might specifically be asking to copy only the file content. Conceptually, anything done to the original by knowing its handle only can be done to the copy as well, supposing that there are "get" calls to match all "set" calls on handles.