What is the test for using talismanic force to induce a witness to withhold testimony?

" 'There is, of course, no talismanic requirement that a defendant must say "Don't testify" or words tantamount thereto, in order to commit the charged offenses. As long as his words or actions support the inference that he . . . attempted by threat of force to induce a person to withhold testimony [citation], a defendant is properly' convicted of a violation of section 136.1, subdivision (c)(1). [Citation.]" (People v. Mendoza (1997) 59 Cal.App.4th 1333, 1344, superseded by statute on another point as stated in People v. Franz (2001) 88 Cal.App.4th 1426, 1442.)³