please refer to Jon Gold, The Dharma's Gatekeepers, p. 182, for the verse
from Sakya Pandita that explains this. Māyā here in the sense of "deviousness, stealth," not
illusion:

"Geese .. by advancing stealthily ... attain the object of their desire..."

Matthew Kapstein
Directeur d'études,
Ecole Pratique des Hautes Etudes

Numata Visiting Professor of Buddhist Studies,
The University of Chicago