JAGTHEGEMINI
[12] Conqueror
"Useless" may be hyperbolic, but there are sound reasons for why GI went unused in these games.
SC1 and SC2 suffered from many of the same issues in regards to GI. The movement in those games was off the charts, knockdowns meant virtually nothing, and the number of situations where GI is preferable to stepping could be counted on one hand. That's not even getting into 2G.
In SC4, I estimate that more than half the cast had aGIs that could be used to counter moves like Amy 66A, and these aGIs guaranteed damage. Outside of countering these types of reactable but otherwise unavoidable moves, GI served little purpose. Plus there was the clusterfuck that was the perfect impact system. Although ironically SC4 is the only one to have a bug-free GI implementation.
But in the first SC there was no 2G afaik... There were problems with the GI-system but not on a SC2 scale. And knockdowns meant sometimes something ´cause in the first SC there were already techtraps, albeit only a few one.
And in SCIII arcade the broken GI-system from the console version was fixed. So sad we in the west never really got to experience that game...