What that matters is what trader are you.
Scalpers will prefer to use the 15 minutes candles instead. But day traders will prefer the 4 hours candles. Swing traders will prefer the 4 hours to a day or 1 week candles. Holders will prefer the monthly candles also.
Based on his statement he said its a long term trading weekly or monthly meaning it's a swing trading.
The reason why almost every indicator works is that it produces more reliable signals and fewer faulty signals.
However, in a short time frame, not all indicators will work perfectly without patterns,strategy and etc... fundamental will help for making decision but it doesn't always work on short time frame.