An interesting aside from Burton P. in the Employment Appeal Tribunal, in which he emphasises the importance of abandoning a case as soon as a party realises (or is advised) it has no real prospect of success - see para. 39 of the decision.
He adds (at para. 40) that a useful test (probably more applicable to appeals than hearings before the ET) is whether the other side have been called on to respond ("the best test in our judgment as to whether case really has no realistic prospect of success is whether a case is so poor that it does not even get the other side up on their feet").
Thorpe v Eaton Electrical Ltd