block in current mode in RAC

Hello ,

If a block is requested in current mode in RAC by another instance I understand that block lying in sga of that instance (master instance of that block) sis transferred as such to the requesting instance however in Consistent read mode this would rollback the block first if it's uncommitted

If block in current mode goes to another instance that would cause a inconsistent read since it's not committed and going to the requesting instance.In what circumstances a block in current mode can be requested ?

Best regards,

Vishal