Riding shotgun with big banks over interest-only lending has paid off for APRA. The new flow rate, as a 23 per cent share of all new lending, is a material fall from 30 per cent for three banks and 50 per cent at Westpac.P&I loans are popular, being better for managing risks and giving a user a chance at a very lowly priced variable rate loan. Banks have also dragged many borrowers over from interest-only in recent years, often at the customer's request.The interest-only fizzer, Banking Day branded macroprudential policy in July. This was the Monday after APRA, the RBA and ACCC stepped out one week to produce a tory version of a royal commission.Prosecutions are not just pending but underway in Westpac's case over short rates antics.Westpac will find the responsible lending case ahead in 2018 a harsher matter than this month's rate case.The considered ignorance on debt on income ratios in banking will soon yield. Who knows, maybe in the lee of an Australian industry failure.