I'm not a barrister so not been in that position. I have had cases with me as a (corporate) client and that my barrister and legal team thought was strong and would win. And then lost. I have had cases settle at various points including on the Sunday before the kick off of the trial on the Monday....Have you ever had a brief that you were 100% certain you would win? The follow up question is did you win it?
I would imagine this is quite rare as there is absolutely no certainty in these matters, which is why I haven't been entirely convinced by the bullishness expressed by the club.
As I have said before, even the strongest case can lose and no case is better than 70% chance of winning.