Mother Tongue Change Weightage in PSLE Exam

I refer to comment by Mr Chen Shi Ping Zaobao reader dated 24th April, 2010.
MOE 2009 PSLE results, % pupils who "A" & "A*":
English 43.9
Chinese 81.1
Maths. 43.3
Science. 42.6
Assuming the above data is accurate, Chinese language is our pupils
best performing subject, why then the need to change as proposed by Dr Ng Eng Hen on
Chinese Language PSLE score weightage?
More puzzling, despite with a 81.1 percent, significantly higher than the
other three subjects, why so many kids these days " hated" to learn Chinese and great discussion going on with challenges in the learning of Mandarin.
I thought Singapore pupils scored among top in the world ranking (Singapore ranked 4th among 45 education systems”- Progress in International Reading Literacy Study -PIRLS, 2006)reported in Maths and Science - why aren't they performing better in Chinese Language. Guess, it's all about marking standard setting
and statistical moderation to create a more presentable "big picture".
Unknowingly, the MOE is confusing the public here - damage will be done to a generation of Singaporeans. Education minister needs to clarify the statistic and the new policy on reduced PSLE weightage on Mother Tongue.