[ThrowawayR2]

The problem is that lazy people use the supposed Einstein quote as a convenient excuse to not know and internalize knowledge about their own profession. You can bet that Einstein memorized the relevant mathematics for his work thoroughly and completely.

[hansmayer]

Oh didn't you know - the legend has it, he was also bad at maths in elementary school, so that kid of your friends, failing the math this year, may be a genius too :)