hi
We can add any kind of buffers in CTS neither small nor large drive strength buffers..But in case of small drive strength buffers the delay will be large..We do CTS in order to match the data and clock path only so If delay is high it seems difficult..
In case of large drive strength,It may occupy large area,may cause congestion...
So it is better to add medium drive strength buffers to overcome this difficulties...
I think this may help u dont forget to click helped..