THE Government's unprecedented move to reveal the name of the next Director of Architectural Services before obtaining final approval was yesterday defended. The chairman of the Public Service Commission (PSC), Augustine Chui Kam, said Kenneth Chan Yat-sum, 53, was such a strong and sure choice he agreed to an early announcement. Secretary for Works James Blake said after Wednesday's promotion board meeting that Mr Chan would take over the 1,800-strong department when Paul Corser retired next month. Mr Chui disagreed that the early announcement had turned the PSC into a rubber stamp. ''The decision is still subject to the approval of the PSC, but I think it is useful for Mr Blake to exercise his discretion to announce the Government's recommendation to dispel recent rumours which have upset staff unnecessarily,'' Mr Chui said. Rumours suggested the new director would come from outside the department, arousing strong opposition from staff associations. Although the PSC and the Governor, Chris Patten, could overturn the recommendation to appoint Mr Chan, Mr Chui said it was unlikely as the choice was not controversial. Mr Chui said the PSC would make the decision as soon as possible.