You're describing "fluent programming" ("it().shouldEqual(x)..."). Unfortunately it's not just unit testing frameworks where this nightmare exists. Plenty of production code abuses the builder pattern to have this "it's like reading English" stuff.
IMO, it only falls apart (and becomes such a nightmare) because of the imprecision of spoken & written word. Computers don't understand idioms, colloquialisms, and the like, and so non-technical staff are tricked into thinking a language/program can do more than it actually can do.