Solution : https://service.sap.com/sap/support/notes/541121 (SAP Service marketplace login required)
Key words : 
front end increased quadratically, front end patches listed, front end correction, front end patch, drag&drop operations, total load process, takes unacceptably long, 0a frontend patch 10, 0b frontend patch 04, frontend patch
Related Notes : 
       
| 577844 | Accelerated processing when you expand structures | 
| 559043 | BW 3.0B Front-End Patch 05 | 
| 537589 | BW 3.0B Front-end Patch 4 | 
| 524827 | Advance information for BW 3.0A front-end patch 10 | 
| 197460 | BW Frontend Checktool sapbexc.xla |