Treip's insight is all the more remarkable because her apparently substantial opening chapters are really rather scrappy as regards both the theory and the practice of allegory.
The loss is apparent if one compares the results where Treip does work out her ideas fully, as in her critique of Bacon.
Treip's grasp of allegory is so subtle and far-reaching, not to say insidious, that she may seem to assign all literature to the allegorical mode.
It is a measure of Treip's success that, though her treatment is involved and largely based on minutiae, with few sustained accounts of pre-eminent passages and actions, it is compelling in its argument.
These are the most notable of many felicities of approach, whereby Treip traces in sensitive detail the levels of signification in Paradise Lost: how much in the poem 'stands for' or incorporates how much more, and by what means.