Intra-word switching occurs within a word, itself, such as at a morpheme boundary.
The problem of such an analysis is the large number of morpheme boundaries typical for agglutinative languages.
Vowel groups can occur in the morpheme boundaries.
This tendency to prefer adjacent high vowels to be identical also spreads across morpheme boundaries within a word.
However, when morpheme boundaries come into play, vowel length can sometimes distinguish otherwise homophonous words.
The second is predictive gemination of initial consonants on morpheme boundaries.
Interestingly, it may be that these effects help to preserve morpheme boundary and identity information.
Kari (1989) and elsewhere uses + to indicate morpheme boundaries.
Synchronically, the assimilation at morpheme boundaries is still productive, such as in:
Stop germination across morpheme boundaries almost always results in simplification to a single phoneme.