We observed that the Contractor had set the Terminal Float to 0 (planned Completion = Completion Date) since the very first submitted programme. Since then, every revised programme showed a delay. This becomes a problem that everything seems to be critical and difficult to monitor the progress. Yet, the first programme (with 0 Terminal Float) was accepted, so we cannot undone and no NEC clause says they cannot do it.
What’s the trick/benefit for the Contractor to set his Terminal Float to 0? For having higher probability to get more CE (EOT/Money) ?
The Completion Date and Planned Completion should be independent of each other. The first is effectively a target. The second is whether you think you will hit the target or not. Your statement that ‘everything seems to be critical’ is a bit worrying - it suggests that Completion Date is being used as a constraint in the programme, which it shouldn’t be.
As for process, there is nothing intrinsically wrong with the two dates being the same.
I don’t see any particular advantage to having zero terminal float, because extensions of time are assessed as the delay to Planned Completion, not the delay to the Completion Date. Therefore if a CE happens here and the Contractor had no terminal float before, they should still have no terminal float afterwards.