Ni for an ISTP is tertiary, and not really the same as auxiliary, like an INTP's Ne. (though some will point out Jung spoke of both as "auxiliaries"). So it won't come out the same, aside from the fact that the orientation is opposite to begin with.
The tertiary won't be as confident and "parental" as the auxiliary. It's more about ego defenses and "relief".
Ni won't be about exploring multiple possibilities like Ne, but rather zeroing in on an internalized pattern to guage situations by. Ne is "informative" in communication (basically, softer or "light and airy"), while both Ni, when "preferred", in addition to S and T together, are "directive" (more serious and task focused).
So the whole style of interaction will be different. The Auxiliary being (supposedly) "underdeveloped" with the tertiary filling in, won't change all of this. (And not sure how accurate that is anyway; these so-called "loops" would likely be at certain times only, anyway, when a tertiary defense needs to fill in for a situation the auxiliary cannot solve).