I'm going to Biarritz on friday - will take my kit - not that optomistic - but you do get teh odd day when the wind comes in and you'll have a great wave riding day
You can kite at Cap Ferret - just not in the swimming zones - lots of waves - Bidart....in summer - no. You can Kite at Madragues Anglet beach after 7 pm in summer - and I've kited at Tarnos north of Bayonne - and there is a Kite beach at Seignosse - its not windy and not many places you are allowed...
Also the official LCL breaking strain is less than the bridle lines so they break rather than the bridles or attachment points......or so the theory goes