Ann: Syntonic Carrier Progress and Performance, page-81

Depends what you're looking at. Everybody has individual methods they adhere to but personally i feel daily highs and lows don't account for too much whilst looking at horizontal support/resistance. You can see i refer to support as 1.2c rather than the wicks that shoot to 1.1c as it's the open and close that are important. The wick to 1.1c shows me that particular price was hit twice but support pushed it up the same days to the critical 1.2c level.

I draw trendlines both inclusive and exclusive of daily highs/lows and open/close price and all combinations between. The more obvious they are the bigger the effect on the SP.