Hermione Wrote:
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No matter
> the identity of the sailors, was such-and-such a
> route feasible?

Not with a balsa raft or any known boat from South America, Central America, or Mexico. Here is what is feasible:
[www.hokulea.com]
"Hokulea has voyaged traditionally since 1976, sailing over 150,000 nautical miles throughout the Pacific."
Scroll to the bottom of page to see all the feasible routes since Heyerahl's era. This craft can do it all, it can sail against the current, wind, and can also be paddled to keep it from wrecking on a reef or land in a sheltered cove.
They did capsize it once early on during the learning curve and sadly lost a crewman, but since have been doing impeccable voyaging.

[en.wikipedia.org]
Once this man made it across the Pacific in a 23 foot boat, it is now known even a smaller craft than the Hokulea could work also, but notice he motored out far enough to catch the right winds and equatorial current as did Heyerdahl.

Another feasible route since Heyerdahl is:
[en.wikipedia.org]
"In 1978, Geordie Tocher and two companions sailed a dugout canoe (the Orenda II), based on Haida designs (but with sails), from Vancouver, British Columbia, Canada to Hawaii. The dugout was 40-foot (12 m) long, made of Douglas fir, and weighed 3.5-short-ton (3.2 t). The mission was launched to add credibility to stories that the Haida had traveled to Hawaii in ancient times. Altogether, the group ventured some 4,500 miles (7,242 km) after two months at sea.[21][22]"
So the experimental work showed it could be done with a wood dugout, but the oral tradition needs backup DNA or some unequivocal artifacts to prove it.

Robinson Crusoe luck.
Heyerdahl didn't succeed in doing anything more complicated than what monkeys accomplished crossing the Atlantic from Africa to the Americas or hippos getting to Madagascar...luck is wonderful stuff.
I have a hard time wondering why anyone would think a lucky Robinson Crusoe did anything at all.
So the only human ingenuity that counts is from those people who *knew* they could sail against the wind and currents, suspected there was land out there from bird migration like knowing Hawaii was there (Heyerdahl had a map, the first people didn't) then headed for it knowing they were able to land cargo or populations in spite of the surf without killing themselves (most of the time) and get back to the point of origin if they had to for some reason.