Jedi to answer your question. The cart is for ground handling. It can be used for launch. It was used for that in the beginning. It was three wheel then and was unstable with wind conditions.
I use the special trailer for direct launch and the cart is used to move from the trailer to the hanger (garage)
If Oshkosh 18 is made possible for me. I will need to bring the cart ,the launch trailer will not be there with me.

On the float I hope no additional step is required.The floats will quickly be above water.