This is according to Cascade when I looked into buying one:
The Dyna has four standard curves. Curve 4 is the same as stock and 1-3 are more aggressive than stock. Mike told me it is fine to advance the timing plate to +4 as long as I did not use curve 3.
Using a timing plate at +4 and the Dyna on curve 4 is the same as +4 with the stock CDI. However, using a timing plate at +4 and curves 1,2, or 3 is NOT the same as stock.
Travis (Bigboybanshee) posted the curves on here a while ago, I will post them when I find them...