Spot on 2a.

I'd like to add to this Greg Scarpa's status as a top-echelon informer, as written in his documents.
First of all, Greg Scarpa was attributed by Colombo squad case agent Lin DeVecchio as being the one behind most of the Title III wiretaps on the Colombo's hierarchy and capos. If "half" of all mobsters were cooperators, then there'd be a lot more people than Scarpa that could secure the Title IIIs.
"Over the course of the past five years, this source had furnished vast quantities of singular information concerning the Colombo Family which has directly led to 17 affidavits in support of Title III intercepts, and 50 re-authorizations of these intercepts. As a result, the NYO in October, 1984, arrested the boss, underboss, three capos, the former boss, three members, and two associates of the Colombo Family (NY 183-2836 "Eclipse Star", NY 183A-2636 "Starquest")."

"This matter involves the indictment and subsequent arrests of all the bosses of each of the five LCN families in New York who compose the "Commission" as well as two underbosses, a consigliere, and a high ranking soldier. This investigation and subsequent predicate violations are based upon Title III intercepts which have provided the necessary facts to support prosecution. These intercepts particularly from the Colombo and Genovese wires are directly attributable to the probable cause initially provided by this source. Therefore, not only has information directly from this source caused the arrest of at least 30 major members of organized crime, but has resulted in the arrest of every boss of all five LCN families in New York.
"The above represents only a small portion of the quantity of significant information provided, which if fully documented would require a lengthy summary report. The source has been paid, over time, relatively small sums for this information. In fact, since re opening, the source has only been paid a total of (redacted) for services and expenses. The overall sum of money is certainly not commensurate with the high quality of the information, considering the numerous indictments, arrests, and sheer amount of singular information which would not have been available from any other source. The result is the saving of countless thousands of man hours in investigative time, and window into the inner workings of the most significant organized crime group in the country.
"Furthermore, the amount requested represents the FBI's appreciation of not only the information, but the high degree of risk assumed by the source at every contact while so doing. Sources of this caliber are extremely rare in the FBI and serve as a tribute to the Informant Development Program in the Organized Crime Field."
- Greg Scarpa's file.

There's no question that Scarpa was, without a doubt, one of the highest ranking cooperators of his time, at least in the Colombo Family, and crucial to the Commission Case. If, as OakasFan has always maintained, "half" of all mobsters throughout history were cooperators, than Scarpa would have no way received the amount of recognition in the Commission case.
Scarpa's accolade and recognition in the Commission Case (spanning all Five Families) pretty much disproves the notion that the top-levels of all five families were swimming with undercover informants.

Do you see what I'm saying, Oak?