> You claim no technical skills are useless then claim that you didn't need (use) 90% of them. Restating their (apparent) point more explicitly: there are no t

> You claim no technical skills are useless then claim that you didn't need (use) 90% of them. Restating their (apparent) point more explicitly: there are no technical skills that have probability 0% of being used; there are many (most) technical skills that have probability less than 100% of being used. There are cost-benefit tradeoffs to consider, but assuming the cost is low enough, it's better (useful) to have it and not need it than need it and not have it.