Edberg did have a fast twist/kicker, when he wanted to hit 110. He could vary it down like a rheostat down to 65mph, used more arc, and really kick it up high.
And kick serves are most effective when HIT DEEP right at the service line. It kicks higher on deeper serves, having more arc and distance to cover, causing higher bounces. Short kicks are for ANGLES out wide and short center lines.
Yes, probably the best, most consistent second serve ever in tennis.