This section of the server docs needs to be updated:

https://access.redhat.com/documentation/en-us/red_hat_jboss_data_grid/7.1/html-single/administration_and_configuration_guide/#configure_transactions_remote_client_server_mode

While the Hot Rod client does not support transactions directly, if a customer wants to use conditional operations (conditional replace, putIfAbsent, and conditional remove) they need to enable locking appropriately. This JIRA also applies: https://issues.jboss.org/browse/ISPN-5691