I tell you what - if I was charged with murdering my baby in premeditated cold blood, and if I knew that in fact my baby had died in a *drowning accident* and that I had covered up the death in a panic (or for whatever reason), I would most definitely take the stand to testify in my own defense, especially given the DT's OS.
If, as the defendant, I was telling the truth regarding the circumstances of my baby's death, I personally would not be afraid to tell my side to the jury. In fact, I suspect I would insist upon testifying if the *theory* my DT had put forth was true & accurate.
I know a defendant's choice to testify or to not testify is not evidence of guilt or innocence, and the jury is instructed accordingly, but still - if it were me...
But then again, I'm a truthful person.