Guessing I'm the last guy who should weigh in here since I still get lost on a map of the ancient world, but your professor sounds like she has been burned one too many times. My gut says you are right though, and history backs you up, because nobody thought Linear B would fall either until some guy stuck with it and cracked it. Those Indus texts being short is a real problem, no question, but short does not mean hopeless when you have thousands of examples to compare side by side. Computers are stupid fast now and they will spot patterns in those signs that a room full of grad students would miss in a lifetime. Give it ten years, a couple of good digs, and somebody stubborn enough to connect the dots, and I would bet on the script losing.

Whisk works because it develops gluten, it doesn't just mix. That's why your dough got smoother, not some fluke with your recipe.