Things can change too quick to commit to such a long crossing in an open boat even if the present conditions seem OK.

This spring I was on a large MI lake (Higgins) and enjoying the flat surface conditions to peer down into the depths at a drop off. I noticed a slight breeze riffled the water and we couldn't see down much anymore. Less than 10 mins later and it was a good thing we were in sea kayaks with spray skirts.

I sat in on a Canoecopia talk 2 yrs ago and ever since then its bothered me. The speaker mentioned some people that had needed rescued from L Superior. The couple was in the audience. Rather than being humbled about the decision they made to try a long crossing in a tandem kayak alone. They seemed to enjoy their 15 mins of fame. Adding some misinformation too, such as, it was against the law to bring bear spray into Cdn. I argued the point. But he was convinced he was an authority on the issue, since he was the one getting all the attention.