Fritz wrote on May 24^th, 2016 at 1:36am:

Thanks Old Salt.  Frogg Toggs when it's warm and Gore-tex when it's cool sounds good.  We go in July.  On a the 274 rod portage the water running in my sleeves from the gunwales and sweating left me soaked inside as much as out.

I wouldn't wear a rain top under a canoe in a rain unless it was really bad. The canoe is your top, for the reasons you mentioned. It's always a judgement call as to what to wear when...

I usually carry packs, while partner carries canoe. In July, I would just be grateful for the refreshing shower, and not wear rain top. Water is not one of my many allergies. It's only a concern when hypothermia is a concern. Just break out the Ivory at the end and scrub up. 8-)