OK I found some info.
I did search before posting but had no luck.
Then I tried again and found an old post on this issue.
THCOn () does in fact not work even though it is documented in the above manual.
However startTHC does work
And it is also in the manual. Should have looked a little harder.
EDIT: that leaves the implied question above.
Is there another or better way to have THC default to the ON condition?