I like the book fine, but suspect it works best for people whose enneagram type is consonant with their MBTI type. I found that I related more to the NT "in the grip" descriptions than I did to the NF "in the grip" descriptions. I think that makes some sense given my enneagram type.
I found the IxFP description VERY enneagram 9 heavy. The basic concepts apply though. I relate as much to the Ti and Ni descriptions, both in describing the grip scenarios and the general type. If I didnt know better, then besides the "J" parts about INFJs, I'd probably identify as INFJ just based on the info here.
The parts about INFPs and cleaning and organizing to de-stress as related to inferior Te was
. I show more inferior sensing when it comes to ways I de-stress. I'm indulgent (food, drink, retail therapy, sleeping, etc) and/or find it soothing to stop thinking and just absorb details in the atmosphere for once.
I read something interesting on this website:
The Impact of 'S-N Blindness' on the Distribution of MBTI Types Across the Enneazones
It criticizes certain enneagram and Jungian type correlations and proposes another view.
This is what it says about INFPs:
....we would conjecture that INFPs that gravitate toward zone 9 are being pulled there by their inferior fourth function (thinking) which they share with ISFPs, who are also pulled there; while INFPs who gravitate toward 4 will be pulled there by their underdeveloped third function and have issues that are more similar to the INFJ's inferior sensing...
Basically, INFP e4s tend to be quite weak on Si, as a major aspect of being e4 is weak sensing. This is not sensing as some imagine, as 4s may be asethetes and have a special connection to sensory experiences because of heightened feeling. But sensing here means being grounded in factual experience (closer to Jung's meaning), which 4s are not, instead being caught up in fantasies and distorted emotional interpretations. This may create similarities with INFP's "in the grip" secnarios with those of INFJs.
What this would mean for INFP 5s....I would guess that there would still be inferior Te insecurity over competency and harsh criticism towards oneself (and others). But while 9s may have more insecurity over being organized and logical in their thinking, I imagine INFP 5s may have more insecurity regarding meeting social protocol, almost a faux inferior Fe; aka, the way they measure up to impersonal Te standards in terms of being highly productive, energetic, and gregarious. There is also a Te valuing of Feeling which says it has its place as some sort of feminine role, and Fi (especially in a 5) doesnt really fit that. So one still experiences inferior Te as popping up to undermine, which is the main theme to me for Fi-doms - Te very directly undermines Fi, more than other types' inferiors undermine them, because of the very nature of Fi and Te thinking.