KO count - convert RC to TC for betting?

The simplicity of the unbalanced KO count is appealing, but using the RC alone for betting strategy doesn't seem accurate. Is there a way to convert this to a TC for betting? In BJ Attack, p. 287, Don Schlesinger mentions a related true count called the TKO, but I can't find this anywhere. Does the TKO provide a way to convert a KO RC to a TC, is it a balanced count that uses the KO card tags, or something else entirely? TIA - Mark