>>529542038
>>529542101
>>529542181
>>529542240
the 4m only gives you the improvement of a ryanmen shape for when your draw 5m, BUT discarding the 4m makes it more likelier for the 2m to come out if you draw 5s or 8s and decide to go for a shanpon wait, but the 3m wait with the penchan wait would also be more likelier to come out. drawing 1m or 2m even gives us a direct suji trap. this is one of the rare cases where I would say the additional tile acceptance is just not worth it