CS fundamentals are nice to know, but how often does one implement something custom like BigTable/Colossus from scratch vs. buy/use OTS? The support/scalability/technical debt/unforeseen costs of implementing something entirely new is typically much greater than using adequate "lego" that already exist.
Judgement of cost/benefit DIY vs. OTS can be gained (hopefully) without too much wasted effort, time, money, morale & business life-expectancy.
CS fundamentals are nice to know, but how often does one implement something custom like BigTable/Colossus from scratch vs. buy/use OTS? The support/scalability/technical debt/unforeseen costs of implementing something entirely new is typically much greater than using adequate "lego" that already exist.
Judgement of cost/benefit DIY vs. OTS can be gained (hopefully) without too much wasted effort, time, money, morale & business life-expectancy.