Ang's argument is that there are 4 types of corruption - Petty Theft (eg. policeman takes a bribe), Grand Theft (eg. a Governor embezzles from the state pension fund), Speed Money (eg. business pay bribes to speed up processing of a permit), and Access Money (eg. pay bribes to get access to the bureaucracy).
Ang's thesis posits that China's comparative ability to somewhat temper Speed Money corruption was the primary driver for China's economic growth (eg. via SEZs and allowing foreign corporate structures to leverage Hong Kong).
This is not meant to be treated as a positive though. Ang points out that China still has an active problem with Access Corruption due to the chumminess between regulators and politically connected firms which can lead to systemic risks (eg. Evergrande Crisis):
"China provides a sharp illustration: by enriching capitalists who pay for privileges and rewarding politicians who serve capitalist interests, access money perversely stimulates transactions and investment, which translates into GDP growth (Ang 2019; Ang 2020, chapter 5).
Yet this does not mean that access money is “good” for the economy—on the contrary, it distorts the allocation of resources, breeds systemic risks, and exacerbates inequality. The harm of access money only blows up in the event of a crisis: for example, America’s first great depression of 1839 (triggered by risky public financing and state-bank collusion) (Ang 2016, chapter 7; Wallis 2000, 2001), the 1997 East Asia financial crisis (Kang 2002), and the 2008 US financial crisis (Baker 2010; Igan, Mishra, and Tressel 2011; White 2011; Fisman and Golden 2017; Fligstein, Brundage, and Schultz, Forthcoming)"
- "Unbundling Corruption: Revisiting Six Questions on Corruption", Yuen Yuen Ang 2019