[giantg2]

Mainframes are expensive because they're niche and basically a duopoly. The companies supplying them know their days are numbered and charge high prices before the market goes dry.

In my experience, the quick teams only learn the surface content. A lack of depth tends to result in more errors down the road and poor architecture. But I guess it doesn't matter since half your team will jump to the next project company in 2-3 years anyways and take that knowledge with them.