> it will be gibberish to about 99% of all mathematicians out there .
If you'd said "programmer" instead of "mathematician," I'd agree with you. As it stands, though, those pages are reviewing just basic algebraic topology, which any practicing professional mathematician would know to some degree. These days, it's taught to top undergraduates and almost universally to first-year graduate students; it is also typically prominent material on PhD qualifying exams in mathematics.
If you'd said "programmer" instead of "mathematician," I'd agree with you. As it stands, though, those pages are reviewing just basic algebraic topology, which any practicing professional mathematician would know to some degree. These days, it's taught to top undergraduates and almost universally to first-year graduate students; it is also typically prominent material on PhD qualifying exams in mathematics.