Learn English – Can an “opinion” be right or wrong

In my opinion, the adverb enough used in this sense creates a conversational rapport between the speaker/writer and listener/reader. In strangely enough, interestingly enough etc., the enough might mean "enough to go so far as to consider it such". The reason it's used is perhaps a fear that the addressee might not feel the described circumstances really warrant the qualification strangely/interestingly/etc. By using it, the speaker/writer acknowledges that their listener/reader is right to think that, but that the circumstances really can be considered such for the sake of their conversation.

In any case, this enough is not used in a formal register. When it is used in a formal setting, it signals a (temporary) lowering of the register.

Just my two cents.

A hypothesis is a guess, based on data or logic of some kind.

So, if your hypothesis is: It is pointless to brush your teeth in the morning because no food has been eaten, not eating serves as the logic that bolsters your guess.

For a hypothesis to be viable, it needs be testable.