The author never assumed that clergy only recorded religious activities of peasants. The assumption is that the level of religious dedication was exaggerated; but this allows for plenty of records related to nonreligious things.

This has no clear impact. We don’t know how the amount of time spent among peasants relates to the possibility that clergy exaggerated the level of peasants’ religious dedication.

This undermines the assumption that the clergy exaggerated peasants’ religious dedication. We would expect clergy to exaggerate other peoples’ dedication, too. But if they didn’t exaggerate for merchants/nobles, that suggests they might not have exaggerated for peasants, too.

This has no clear impact. We don’t know whether historians have consulted all relevant surviving records. Also, even if historians can’t develop a reliable account, that’s consistent with the author’s position that we have reason to doubt the prevailing view.

The author already recognizes this possibility. His position is that these descriptions are likely to be exaggerations.