Someone takes a cup containing just the amount of wine for which he must make a blessing after drinking it.
He then dilutes the wine with water such that the blessing is no longer “borei pri hagofen” but rather “shehakol”. See here, question 29 for the amount of dilution required.
He then drinks the mixture so that he has drunk the amount of wine within the time needed to necessitate an after-blessing.
What blessing does he make? “Al hagefen” or “Borei nefoshos rabos”?
He has had the nutritional benefit of the wine but it was not “wine” when he ingested it.
He did ingest it in the normal fashion; it was not introduced, for