The CIS E GTI ignition box and the Digi ECU both have an inbuilt processing delay of about 60*. (If you bypass them, your timing will be over-advanced by that amount and will need resetting to fixed total timing of your choice (31-33* generally for 8v)
With a new distributor there is very little ignition scatter at any rpm. Crank-fire is nice if you build a hand-grenade 14/1+ GT motor which is very sensitive to over-advance. One degree of scatter/timing off by 2* in this app=virtually no power difference around proper setting.
If you set your timing with locked/no advance setup and see several degrees of retard @6k, it's probably your light and not the ignition that is late. (search MSD ignition info which put me present to this and their recommendation for a specific Sears Penske light which made me a believer when I saw my Volvo motor was overadvanced 4* @6500 if I timed it with $$ Snap-On light!)
And, yes-for IT app, advance curve is unnecessary/no help to power in usable rev band.