i studied in literature juglars knew perfectly memorized word to word several chaints and check their size:
http://amediavoz.com/cantardemiocid.htm
more than that, they didnt have paper then so just by listening to it several times from the juglar master should sufice
and compare with todays:
i think we as human are seriously devolving but we dont notice for were doing it all at the same time and slowly
well no wonder, i have deodorant with aluminum air with lead from fuel, teeth cavity feelings with mercury and i smoke cause i saw superman as akid and now cant quit
i think all kind of poisons should be banned