Bathurstwalla
From what I gather, people with the right prerequisites for AE and TT are ~90% from overseas, not holding a HKID card. Vast majority of HKID holders do not have the means or need to meet the AE or TT requirements since they can easily take the AB course if they make it past assessments.
So holding a HKID card would not be an advantage for AE and TT unless you're planning on applying for the AB stream. Especially if you only hold a 'C' code on your HKID, by which case, you will be treated the same as a non-HKID expat candidate - and only AE and TT will be available.
Hope this clears up your questions mate.
Cheers.
J