A terminal list table is a list of terminals, defined either by four-character CICS terminal names or by three-character CICS operator identifiers. It is used principally for routing messages to multiple destinations and for giving limited operational control of a group of terminals to a supervisor. Both of these uses must be rethought in an autoinstall environment. If a TLT lists terminals that do not have TCT entries, because they are not logged on at the time the TLT is used, supervisory operations against those terminals fails. For example, you cannot put a nonexistent TCT entry into or out of service.
Similarly, message routing works differently for individually defined terminals and for autoinstalled terminals. When a message is sent to an individually defined terminal that is not logged on, the message is saved in temporary storage, and delivered when the terminal logs on. When a message is sent to a terminal that is not defined because it is an autoinstalled terminal and is not logged on, CICS gives a route fail condition, indicating that it knows nothing of that terminal. Indeed, if terminal names are generated and assigned randomly, as they may be in an autoinstall environment, the whole TLT mechanism breaks down.