Doubt in glue logic in programming of IEEE 1500

[deepen talati]

I have learned about JTAG and 1500 interface. Then I was learning about how can we program 1500 using JTAG.
Glue logic has been used to get the control signals(WSC) for 1500.
Shift_IR and Shift_DR signals from TAP are the inputs for OR gate and output of that gate is being fed to FF(-ve edge triggered). Same for Capture signals and Update signal except for Update signal FF is not used.
I have doubt regarding flip flops those included in glue logic. What is the requirement for those?
Shift and Capture events occur on the rising edge of TCK while Update event occurs on falling edge of TCK.
By including FF(-ve edge triggered) we will get Capture and Shift signals on falling edge of TCK and Update is already generating on falling edge.
So are we doing pipelining or what? Why we need to do that?

Waiting for your reply. And let me know if my question is not clear to you.

Thanks and Regards,
Deepen Talati