AK, you came in a few months before AC dropped. Since you couldn't do 10-hit Grand Viper, you probably don't remember, but slowdown is in all versions of GG. Arcade, PS1, PS2, and GBA. AC console is the oddball. Instead of occasional slowdown/crashing, it's just constantly sped up. Removal of slowdowns is the probable source of the speed difference. But..
shrug
After AK's first day of playing on the AC cab, I asked him if the Wii version felt like PS2 or Arcade. He said PS2. BUT, then again, people also said AC felt the same speed as Slash (ノಠ益ಠ)ノ彡┻━┻
Back when there was a big debate about keeping Slash for EVO, or switching mid-qualifiers to AC, there were one or two players who said something along the lines of, "AC is an unbalanced bullshit scrub game, people won't have time to adjust to the changes, and the game isn't even the right speed!" But of course the speed remark got overshadowed by accusations that a Guilty Gear game could be anything but the most balanced fighting game in the universe, whose players are so far above the lowly scrubs that they should be herald like gods.
Then they left the scene forever. Meanwhile, Testament's new BnB consists of one move looped over and over again. And I'm too busy chasing "undocumented changes", while Steve H is running on some tables some where.