The third phase in the sequence is not exactly IPF - I would call it Being Delighted In . It’s influenced by Deity Yoga and Attachment theory and IPF itself, but it’s not either of those.
The practice is different from Deity Yoga (aka Yidam) in that you’re noting how you feel as the visualization progresses. That allows for the body & the somatic emotional system to open up in relation to the image and the intersubjective experience of the image delighting in the practitioner.
It’s also focused on the qualities of Love but also Delight which is one of the 5 characteristics of secure attachment (Safety & Protection, Attunement, Soothing & Comfort, Expressed Delight, Support & Encouragement for self-development).
It’s different from Ideal Parent Figure protocol and visualization in that IPF is a structured, guided visualization with Ideal Parent pair - either in a group or 1:1 setting. BDI is more spontaneous and dynamic interaction with an image that doesn’t have to be parental. IPF also doesn’t have “noting” in it.
Here is a recording of a 20 min guided visualization of IPF by George Haas for reference