LONDON, Jan 21 (Reuters Breakingviews) - What’s good for venture capital isn’t necessarily good for venture capitalists. That’s one message from “The Power Law: Venture Capital and the Art of Disruption”, Sebastian Mallaby’s absorbing new history of startup investing. Successful early technology backers invited imitators, making capital into a commodity and empowering cocksure founders. Even as the $1.8 trillion industry breaks fundraising and dealmaking records, its influence over companies may have peaked.