My error, FWIW, I use 10 charts with RTH, formerly the former and 8 charts with ETH, formerly the latter. A right trendline (RTL) is the right side of a channel and this is all that many people draw. If one adds a left trendline (LTL) then one generates channel. IMO, a channel is much more useful than a single trendline. Trendlines and channels add order to 'apparent' chaos and point out that the market moves right to left not up and down. I am not knocking the PA tribe when I say this, not that they would care anyway.Believe I said I trade a 900 second chart and use a 300 second chart as an indicator. The reason for using seconds vs minutes is that with my charting software, which is Ninja Trader, if you use seconds for ETH and minutes for RTH then you can have both ETH and RTH in the same workspace. Otherwise you can't.
I use two workspaces - RTH and ETH, the former with 8 charts the latter with 10 charts. Time frames are 30, 15, 5 for ES and 30, 15, 2 for YM then 1800, 900, 300 for ES and 1800, 900, 120 for YM.
I believe YM very frequently will lead ES in breaking a trend line (RTL) or setting a retrace or reversal point as a prelude to a RTL break. This is not quite a Boolean but it is very close. It is why though I just trade ES, I always have YM to look at. Trendlines are liquid entities that are obviously there to be broken. It is not a question of them working or not working. If there is a solitary spike bar or a breakout failure, then one simply fans the trendline to establish a new RTL. To not get sucked in on these line games, look at where the bar closes in relation to the trend line and whether the break was made with high volume. If the LTL is 'broken' then reset the RTL to match the steeper slope.
IMO the most important thing is to draw a trendline using the method of Victor Sperandeo. It eliminates ANY subjectivity and that is critical. Fuzzy feelings about where/how the line should be drawn will facilitate a bilateral orchiectomy in the most brutal of fashions.