The clearest results-based peak across Istra's coaching carousel belongs to Gonzalo García, whose 18-match spell in the second half of 24/25 produced 29 points at 1.61 PPG — the best rate of any tenure in the dataset and well above the 1.2 PPG mark that signals genuine quality for a mid-table HNL club. García inherited a squad that Tramezzani had steadied through the opening months of the season and promptly unlocked its attacking potential: 7 wins and only 3 defeats in 18 games represents a run that, projected over a full campaign, would have challenged for European places. Tramezzani's own record splits sharply across his two stints — 1.53 PPG over 15 games at the end of 23/24, then 1.06 PPG from 17 games in 24/25 — a meaningful drop that likely reflects reduced squad quality between seasons rather than tactical regression. David Català's 17-match tenure in the first half of 23/24 returned just 0.94 PPG, explaining the mid-season change, while Mislav Karoglan's three-game opening (0.33 PPG) was a difficult beginning to what became a turbulent year. In 25/26 the picture is more layered: Goran Tomić's six-game transition period (0.83 PPG) gave way to Oriol Riera's 23-match stint at 1.35 PPG, with Krešimir Režić opening at an encouraging 1.40 PPG from his first five games.

The Performance Index data adds important texture. García's 0.536 PI stands as the highest of any substantive tenure, confirming that his results reflected genuine dominance — better chance creation, tighter defensive structure, and more controlled possession — rather than fortunate finishes. Tramezzani's first stint posted the second-highest PI at 0.505, consistent with a team playing at a high level in the closing months of 23/24; notably, his underlying quality actually exceeded that of García's predecessor Gonzalo in raw performance terms, though García converted more of that quality into points. Tramezzani's second tenure dropped to 0.418, a significant fall in line with his results decline. Català's 0.431 is the most analytically interesting figure: his team generated relatively strong underlying performance but converted only 0.94 PPG, suggesting a squad capable of playing well but undermined by poor finishing or decision-making in key moments. In 25/26, Riera (0.407), Režić (0.436), and Tomić (0.396) occupied a tight band, pointing to squad ceiling as the primary constraint on Istra's output in the third season regardless of who was in the dugout.