OK, just ran a similar Excel file:
1) 500 one-on-one series of 20 matches (so 1000 rounds; recalcing changed answer by 1% or less every time, so sample is valid)
2) Handicap formula with the 96% factor, rating 71.5, slope 128; using the average of the best 50% of each of the 20 round series of matches
3) I did not round or truncate any scores (just used the actual decimals for all calcs)
4) did this with stroke play with no accounting for adjusting scores / maxing scores per hole (I think this makes it even worse for the high HC)
Results:
a) baseline; both players shoot the exact score every time: Low HC shooting 72 every round wins 100% of the time vs a high HC shooting 82 every time; this is due to the 96% factor
b) same differential; Low HC shoots between 72-77; High HC shoots between 82-87; Low HC wins 56% of the time
c) higher differential for high handicapper; Low HC shoots 72-77; high HC shoots 82 - 92; Low HC wins 65% of the time (that is pretty much the same outcome as the simple grid that predicted 66% to the low HC)
d) really high differential for high handicapper; Low HC shoots 72-77; high HC shoots 82 - 102; Low HC wins 70% of the time

So, low handicapper is better off due to the 96% factor and due to a lower deviation in scores.