It would be really interesting to be able to read an HSSFRow object, clone it, and be able to insert that row at a defined position. This would provide a mechanism that reproduce the Excel behavior when you "copy" a row, and then select an other row, and choose "Insert Copied Cells" command.
I don't expect this to be done anytime soon without substantial code-contribution as part of the bug-entry, if you are still interested and can provide a starting implementation, then please reopen this bug with the proposed changes attached.