... infiltrate so many criminal organizations; One per season might be realistic. Then again it might have been boring too?
"It's the system, Lara. People will be different after the Revolution."
I think that it was noted during the series that Vinnie was kind of a superstar undercover agent with all of his successes. First he took down a crime family, then an international arms/ drug dealer while simultaneously helping to derail the overthrow of a sovereign nation by a rogue CIA operative, who may have been fronting for a consortium of big businesses.
And that was just in the first season. Vinnie Terranova and Frank McPike were superstars.
the way they did it, it makes a degree of sense... it's when you simplify it that it sounds impossible... but his cases involved a varied depth of involvement and time required undercover
he 'made his bones' on Steelgrave after they placed him on Prison for two years to 'backstop' it.
from Steelgrave they kept his cover intact, and he used that reputation to get into Profitt's posse...
from Profitt he went home, and fell into the Pilgrims of Promise as a personal mission
then he was set up as 'security' in the 'Rag Trade' but was injured before he got too deep... Raglin was installed with only a tenuous connection to Vinnie
once healthy he makes a Move on 'Dead Dog' looking like a Low level Mafioso Muscle trying to elevate himself within the organization.
Textiles and Music are two common 'shells' that the Mafia would logically infiltrate either as fronts, laundering, or simple diversification
Come season 3 His Mom had married a mafia Don, both in on his Cover, but keeping it; so his Life becomes his cover as he defends his Step father
Mid season 3 saw half a season of stand alone stories and no real case
Followed by an Investigation from Within so he's not actually undercover
and Finally the only case with no real thread to any others, Volchak / Lynchburg
so he's really only taking on two cases a year...