It may be down to the size of the crab cakes! You will see that they are uncharacteristically quite big and deep which is the problem I think.I haven't seen this episode yet as I am recording them to catch-up later - but I will likely see it tonight and watch with great interest! I've made crab cakes lots of times in the past - Thai style and not Thai style and using fresh crab and tinned crab (on separate occasions). I can't recall having any problem - you are making me want to make them again! I don't think i have any crab cakes recipes on the forum - though I have a recipe for crab roulade, I think. I'll have a look.
The crab roulade sounds interesting! Presumably crab added to the basic mixture or more involved? I wouldn't mind seeing that recipe if it is to hand....although, now I think about it, I might prefer a standard roulade with the crab - and maybe prawn - as the filling mixed into some creme fraiche or mascarpone with a little chilli maybe.