my understanding is that BG moved from an old pay scale and increment system to a performance based pay model common in the private sector.
I understand that basic pay was reset at 85% to 90% of the old average rate. Poorly performing employees will find them selves down. Average performing will break even and really excellent performers will be 10% up on old rates.
The performance pay would depend on individual, team, and company performance.
This package would have involved the trade unions and I'm guessing that the new contracts have a dc pension rather than a db one.
I reckon the whole thing is just a bottle of smoke drummed up by a few lazy journos.