I think I figured out the math
we look at the active, recovery, and hit or block stuns of the first move, and startup of the special
in Gen’s case:
Gen (startup active recovery blockstun hitstun)
st.mk 5 3 20 20 24
mp hands 4
we always assume the move hits on its first active frame. for a single st.mk hit you can figure out the advantage by Hitstun - (recovery + active frames - 1)
st.mk 24 - (20+3-1) = +2 hit advantage TRUE according to the table
st.mk 20 - (20+3-1) = -2 block advantage TRUE according to the table
- notice if a move hit on it is second active frame you will get an additional frame of advantage
when you cancel I am going to assume you disregard the rest of the active frames and the recovery
st.mk -> hands
opponent will be in 24F hitstun and the move takes 4F startup so it easily combos. and with 20F blockstun and 4F startup of next move you get a solid blockstring from cancel
in Chun’s case
blockstun for far st.mp is 13F. mp Kikouken takes 12F to come out so in theory it is a 1F room solid blockstring. however because of the spacing kikouken won’t land on it is first active frame and therefore ruins the solidity of the blockstring. ie the blockstun frames will end before the fireball reaches.
on the other hand close st.fp -> kikouken is solid blockstring because close st.fp gives 17F blockstun and kikouken start at 14/12/10 (lp/mp/hp) and they land in their first active frame(i think) due to chun being too close to the opponent.