Which Groupset?

Found this on Chain Reaction;

I found out the expensive way the derailleur is not compatible with the older 4600 STI shifters. The cable pull ratio is different, confirmed by LBS, so I had to buy the 4700 STI shifters. Direct quote from the 4700 STI page.

"No, Shimano have changed the routing and cable pull ratio on the new 4700 Tiagra so they are only currently compatible with their corresponding 4700 and 4703 derailleurs. They won't work correctly with the earlier generation 10 speed systems."

Make sense as the derailleur look identical to the 11 speed version.