This is coolbert:
Weapons testing in the communist nations with live human subjected to weapons fire not merely confined to the Soviet Union during the Stalinist era and the Cold War.
"Bunkers in Albania"
"During the nearly forty-year leadership of Enver Hoxha [Hoe-cha] of the People's Socialist Republic of Albania, over 700,000 bunkers were built in the country – one for every four inhabitants. The bunkers . . . are still a ubiquitous sight in Albania"
"The prototype for the bunkers was built in the 1950s, with the chief engineer assuring Hoxha that it would withstand a full assault from a tank. Hoxha decided to test it, with the engineer inside, and when he emerged unscathed from the attack mass production began."
I guess fortification design and testing doesn't much more meticulous than that. If your design [as the chief engineer] works, you live, if it doesn't, you die! Get it right the first time.