The IsDependent() call instructs Telerik Data Access to handle deletion of the referenced entities 'logically' but not 'physically'. It does not set the cascade delete on the DLL level bit fires additional queries to delete the entities.
backendConfiguration.Runtime.AllowCascadeDelete = true;
is taken into account only by internally generated constraints in case of multi-table entities or vertical inheritance.
It is not possible to set the cascade delete in associations for the time being.
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