completely simulate the tab key in a remap

[Sweetins]

Hi guys, I have assigned my right shift key to tab using

RShift::Tab

It working alright but I just realised that when I press and hold down my newly assigned tab key (which is Right Shift), it rather doesn't behave like pressing and holding down the original tab key. Pressing and holding down the original tab key sends multiple tab-press but doing the same with my tab-assigned key behaves like I have pressed the tab key once. Am I missing any ingredient in my script? Thanks in advance