Using Tab key as marker/expander?

Is it possible to use the "Tab" key as a word/phrase expander? I notice there's an option under the "Markers" tab in the Instant Text options, but when I try to check "tab", it doesn't appear to work.

Also, when used as a phrase expander, it leaves a tab character after the phrase that has just expanded.

Please let me know if this is possible. Before using I.T. I used programming tool, which expands using "Tab" (similar to the way a command prompt works).

Anyway, please let me know.

regardsm