Not at all.
Players who declined or did not get any better after leaving Tigers, according to me
Nu Brown
Austin Dias
Kenny Maumolo
Madden
Musgrove
Aussie Jim
Kelma Tuilagi
Kitione Kautoga
Liddle
Gildart
Mikaele
Tom Amone
Zac Cini
Mbye
BJ Leilua
Elijah Taylor
arguably Aloiai
Corey Thompson
Esan Marsters
Reece Hoffman
Momirovski
Josh Reynolds
Tui Lolohea
Mahe Fonua
Tim Grant
Pita Godinet
Robbie Rochow
Woods
Ava S
JJ Collins
Rankin
Curtis Siro
Asi Fine
Josh Drinkwater
Matt Lodge
Delouise H
Siti Akauola
Blake Austin
Bodene Thompson
Lamar
James Gavet
Kurtis Rowe
Joel Luani
Ben Murdoch
Ayshford
Sean Meaney
Eddy Pettybourne
Tim Moltzen
Jacob Miller
Tom Humble
Junior Moops
Slow Ryan
Blake Lazarus
Willie Mataka
Geoff Daniela
David Gower
Mitch Brown
Bob Lui
Bryce Gibbs
Mark Flanagan
Groat
Pat Politoni
I mean how far back do I need to go to make the point? You'd be lucky to get legitimately a dozen players that clearly improved AFTER leaving Tigers. E.g. Tedesco, he didn't get better, he was just more successful. Scott Prince did great after he left Tigers, but he also did great at Tigers.