I still dont get it ?
Why would you EVER want to tow a board ??? (your own board that is...)
If you got it in a leash, and wind is too light to relaunch after a kite crash, you are way better off using the board to either sit on (no matter how small), or have your hand around the board when drifting.
This way you have either good overview and plesant as you dont "drown" (well, you know what I mean...), and you can have the board tilted if your arm around it, so when you reach low water or rocks, you dont scratch the foil as you could if towed after you.
Furthermore, as noted, you have a much better chance of relaunching if a gust comes, and at least it is comfortable as opposed to being deep in the water for a long time, where NOTHING is fun anymore