I agree, one would not wait for a DSC call, ever, anywhere.
That's not how it works. You press the button, then make your distress call. You don't press the button and wait for help to arrive.
Also, on the lake, do what you must, cell phone, CH 16, etc.
Can the marine patrol even hear a radio call from every part of the lake? I hear them many times telling people to call via cell phone when a radio signal is weak.
We're now officially off the original topic.