It looks like you guys are claiming that she had a bad boat. According to Guinness World Records Lisa Blair holds the record for
"Fastest circumnavigation of Antarctica by sailboat". She did it in 92 days 18 hours 21 minutes 22 seconds. We know that hundreds of people are trying to beat world records, and there are even yearly races around Antarctica (which we are often pointed to, but the details are rarely discussed). This represents the best boat, so your arguments are pretty invalid.
Like many other topics, we would need to believe in a series of excuses to keep the round world theory together. Instead of providing direct and compelling evidence we are just seeing continual excuses.