While most clip shows are bad, and as has been said before, "lazy writing," this is one of the worst.
The first rule of good science fiction is "never screw around with your basic premise."
In this episode, the alleged reason for the female time traveler's appearance in this time period is to prevent a plague that was "caused by lack of technology."
However, the episode used to illustrate this was one where technology was quite present. Automobiles, electricity, all in evidence.
The writers violated their own premise by using that episode as "evidence" to support the plot.
SHAME on them.
Baaaad writiers! Baaad! Baaaad!
Rated with one star too many.