My instinct is that when it means "to have as an inescapable consequence", entail must be followed by a noun. In all the grammatical examples I have come across this is how it is used — without it being specifically remarked upon. For example:
- This responsibility entails hard work.
- The new job entails regular travel.
- Motherhood entails sacrifice.
But some people use it in sentences like
- When I blush it does not entail that I am embarrassed.
- My lisp does not entail that I cannot be a good singer.
- I am old, but that does not entail that I am also hard of hearing.
Is the usage "... entail that..." grammatically correct?