It is very easy to get into a world of hurt landing in a current / xwind situation.
If current is going one way and wind another bad things can happen.
I have never flown a Robinson but have flown 206 / 206L / AS 355 on floats with lots of actual water landings on lakes and rivers as well as fixed wing flying on floats.
I would be very careful about learning, much less teaching, float operations if you do not get some expert flight instruction.
Lot of helicopters have flipped in rivers and lakes and what is , perhaps, just an embarrassing accident on land can easily become a multi fatality accident in water. You are now inverted, strapped in and in murky, perhaps very cold, perhaps turbulent if in a river, water.
Even a "glassy" water landing on a small lake can easily go pear-shaped.
I am not saying that float ops are dangerous - they just need expert instruction.