It seems that using "fixed attention" for text would encourage the network to periodically summarize the context so far and put it in that fixed column for the

It seems that using "fixed attention" for text would encourage the network to periodically summarize the context so far and put it in that fixed column for the rows below to access. Maybe the reason "strided attention" didn't work as well is that it would require the network to put this context summary in every column lest the rows below be unable to access it. That would waste features since the summary wouldn't vary much over time but would still be stored in full at each step. If this is true, the approach they used for images might actually be inefficient in a similar way.