"At that time we knew that a talented engineer in a tough to get tech was worth about $1.5 million per head. Thus, I knew with relative assurance that since we were going to hire at least 70 people with our Series A money, that our worst case scenario was about a $100 million exit" [1]
ref: [1] http://news.ycombinator.com/item?id=1793095
It is possible for a bleeding edge start-up to include a couple of high value engineers but most of them will just be good engineers (if you are lucky) and some will be less than good.