The writing was already on the wall when Xiao Weiyun, who helped draft the Basic Law, delivered a speech at a Hong Kong seminar in January 2004. In no uncertain terms, he reminded his audience it was under the premise of "one country" that Hongkongers were allowed to practise a different system and run their own affairs.
The mainland professor went on to say Beijing had the power to decide on the development of the city's political system.
His words were not taken seriously by many Hongkongers at the time. Even the then chief secretary Donald Tsang Yam-kuen, who headed a taskforce on political reform, said the views of the visiting legal expert did not represent those of Beijing.
Xiao died a year later. Ten years on, the same stance was reiterated in an unprecedented white paper issued by the State Council on Tuesday.
The document stresses that the high degree of autonomy Hong Kong enjoys is subject to the central government's authorisation. The city has no "residual power", it says, no room to manoeuvre in areas that Beijing has not overtly granted to it.
The use of the term harks back to a similar message sounded by then National People's Congress chairman Wu Bangguo in 2007. Noting that China practised a unitary system of government, Wu said the "high degree of autonomy" was not inherent to Hong Kong; it was granted by the central government.
In the first few years after the handover, Beijing adopted a low-key approach to Hong Kong as it was confident the city could run itself. The Hong Kong and Macau Affairs Office under the State Council played the role of gatekeeper, guarding against any interference from mainland provinces or government ministries.
But that "non-interference" policy ended with a 500,000-strong protest against national security legislation on July 1, 2003. Since then, Beijing has regularly sent researchers to talk to residents from all walks of life. They then submit reports based on what they see and hear.
The following year, Beijing asserted its power to decide Hong Kong's political system through interpretation of the Basic Law.
With Tuesday's formal document, Beijing has gone the extra mile to set out its unquestioned authority over the city. That is because, according to veteran Beijing-friendly politicians, the central government is unhappy with the deliberate defiance of its power shown by some Hongkongers in the debate on how to elect the chief executive in 2017.
Some pan-democrats call for public nomination of poll candidates, an idea Beijing rejects as inconsistent with the Basic Law.
Wong Kwok-kin, a lawmaker from the Beijing-friendly Federation of Trade Unions, said the central government's unease went deeper than that. "It is unhappy with pan-democrats putting Chief Executive Leung Chun-ying in a difficult position by opposing nearly every policy initiative he has put forward."
Beijing's contention that it holds "comprehensive jurisdiction" over the city worries former chief secretary Anson Chan Fang On-sang, as it may indicate an intention to lessen the high degree of autonomy.
As Civic Party lawmaker Ronny Tong Ka-wah, whose reform plan ignores public nomination, put it, "it's time to stop and take a break". He said: "I won't give up on my proposal, but it is just not time to push forward any plan now, as it could backfire."