As fishy as a truck load of rotting fish from fishville
Taking a 20% cut of the revenue for service provision or being allowed to take / supply 20% of the overall business in direct competition to Third Party suppliers does stink of conflict of interest or open the doors wide to contract abuse.
And that is without taking into consideration that as the Prime service provider they will have oversight and detailed knowledge that is not available to Third Parties and therefore can cherry pick contracts.
Increasingly it appears that Capita are the "undeclared" privatised arm of HMG..... Too many contracts, too little oversight, too little evidence of derived value and benefit and yet the contacts keep rolling in.
Finally mega deals such as these are an anathema that seldom delivers the predicted savings or benefits. This should rightly be thrown on the scrap heap and the HMG forced to rethink.