I’m a firm user of averages, the Heiken Ashi is an average of price between the current and last candle’s price.
..The HA 1min time does not provide enough time for price have large differences to slip
so, as such
The 1 minute HA candle value, is not far enough away from the real open value to be a problem
Now anything higher than a 5min timeframe would be completely dumb to use