Meanwhile the subject of his praise, Mr Patten, was holding his last question-and-answer session with legislators, most of whom have spent the past five years criticising him, but who yesterday "banged him out" - banging appreciatively on their desks as he left the chamber.
Clearly moved by the warm atmosphere, Mr Patten told the legislators that he had "been impressed by the way in which the political dialogue in Hong Kong is conducted with moderation and responsibility and more generosity of spirit" than he had witnessed elsewhere.
Asked what he would have done had he been Prime Minister, Mr Patten, a former Conservative Party chairman, said, "I think, as things have turned out, I'd have appointed myself Governor of Hong Kong".
While Mr Patten was addressing the legislators, Mr Tsang was saying, "I have no reservation about feeling thankful for many of the things the colonial government has done".
This is no small tribute from someone whose brother and sister were arrested by the colonial authorities for distributing seditious literature to their school mates in the late Sixties.
Mr Tsang, one of the colony's most prominent leftists, has spent most of his adult life under Special Branch surveillance.
Listing the achievements of the colonial regime, Mr Tsang said it had produced a "very efficient and relatively corruption- free civil service", and had achieved much in terms of education, the environment and housing. "Many Hong Kong people", he said, "feel thankful for the British Government when they look at the situation in Macau", which is under Portuguese administration.
Mr Tsang even had kind words for Mr Patten who, he said, had made the civil service more open and accountable. Nevertheless he accused the Governor of "being at least partially responsible for some of the most tricky problems we have seen in the past years".
This criticism is mild compared to the characterisation of Mr Patten as "a whore", and "a criminal through history" - standard fare for Chinese officials and their supporters in Hong Kong. However, as his days are numbered, there have been some signs that a more benign view is being taken.
Earlier in the week, Zhou Nan (whom Mr Patten privately calls Joe Stalin), the head of the New China News Agency (NCNA), China's de facto embassy in Hong Kong, and an implacable foe of the Governor, said that he did not hold Mr Patten personally to blame for recent Sino-British conflicts. He stated that the Conservative government as a whole was responsible for changing British policy and putting it on a course of confrontation.
A small attempt at reviving anti-Patten acrimony was made in the legislature's chamber when Ip Kwok-him, a member of Mr Tsang's party, asked the Governor whether he was "ashamed of what you have done". Mr Ip told him that he had "some achievements, but that did not make up for the difficulties you have caused Hong Kong".
Reminding legislators that the Governor is often a bruiser at heart, Mr Patten laid into Mr Ip, whom he accused of getting into his stride for next year's election, and sarcastically assured him that even if he could not win, the new regime would find a seat for him under new arrangements which are allegedly "advancing the cause of democracy".
Meanwhile Mr Tsang indirectly confirmed a remarkable statement by Wong Man-fong, a former NCNA official, who recently told an academic seminar that the Chinese government was lobbied by leftists in Hong Kong in the Seventies; they did not want China to resume sovereignty over the colony. Mr Tsang said he was a small potato in leftist circles at this time so was not aware of any lobbying.
However, when China announced that it would resume sovereignty, in 1981, "we thought it was a nonsense", said Mr Tsang. They believed that Hong Kong was of more value to China as it was and therefore could not understand why Peking wanted to change the status quo.
The tenor of Mr Tsang's remarks are in marked contrast to those of China's recently acquired allies who were once pillars of the colonial establishment. The converts, who were supporting the colonial regime while Mr Tsang was fighting it, are scared about making the smallest suggestion that Britain contributed to Hong Kong's success.
n (AP) - Francis Cornish, a career diplomat, will be Britain's first consul-general in Hong Kong after it reverts to Chinese rule at midnight on 30 June, the Foreign Office said yesterday. Mr Cornish, 55, who has been senior trade commissioner in the colony since 1993, will take up the post on 1 July.