From my personal experience:
I have regretted countless things I have said [and written!!].
I have almost never in my life regretted remaining silent.
I have in fact been so thankful for all the times I remained silent [and when Mr. Verbose Loquacious Al Ehrman remains silent it is rarely for lack of what to say - for better or for worse...].
Lesson: Silence is golden.
Avos:
שמעון בנו אומר, כל ימי גדלתי בין החכמים, ולא מצאתי לגוף טוב אלא שתיקה.
