Our recollection is actually very similar, it's just that I was making a slightly different point. Gagne's defensive rep varied somewhat, but basically I remember it like this: Average range that grew, either in practice or just by reputation, to above average. Excellent hands and positional awareness, and one of the best shortstop arms in either league.
While admittedly limited as a stat, Gagne's Range Factor per 9 innings history exactly mirrors the perceived mid-career increase to significantly above league-average range, for what it's worth. Fielding runs above average shows his defense was about 7 or 8 runs better per season than the rest of the league on average. And despite his hacktastic approach at the plate, he managed about 2.5 to 3 wins above replacement per season throughout his prime.
My point was that because Gagne played in the era of Ripken, Ozzie, and Barry Larkin, "above average" looked fairly pedestrian by comparision.
To lend a little more historical context, there are only 12 modern-era shortstops elected by the BBWA to the Hall of Fame. That's almost exactly one per decade. Gagne played almost his entire career with 3 of those 12 guys in the league and in their primes. It set the shortstop bar for Gagne's era ridiculously high, and made it harder to appreciate how good he was despite being nowhere near the players they were.
Interesting note on the physical similarity. Haven't seen Dozier in person, but my impression was that he is stockier than the whippet-lean Gagne. May have something to do with today's uniforms. Gagne was probably a better athlete with just a bit more power and speed, plus a much better arm. But I'm hoping Dozier regains his minor-league batting form and end up with the better eye at the plate, and that would go a long way toward closing the gap in their values.

