So I was wrong (won't be either the first or the last time). In various churches, the sequences of introits, of collects, of epistles, and of gospels themselves have been preserved. But in all cases -- Roman, Lutheran, Anglican -- the interrelationships between them have been scrambled. In the Tridentine missal, the only mass, after Pentecost, that preserves everything is The Second Sunday (although the collects, epistles and gospels are well preserved in the BCP).
Older missals -- such as that of York -- make this perfectly clear.
The reason the scrambling and jumbling appears to make no real difference is that all of these Sundays after Pentecost are but variations on a single theme. But it would be nice to verify that, in a thorough fashion.
Frere provides the following reckoning of "the 26 Gospels in question" (pp. 114-115):
P. S. That last entry is supposed to read "Cum sublevasset." The theme I referred to? Providence -- De la confiance en Dieu.