I agree, looking at multiple time frames can cause trouble.
I think it's because the active trend does not care much about higher time frames, so you should not.
A current example : the 3 months trend (I don't know how to call it, saying medium term means little to most of us) is down.
I remember I wrote about this rising wedge being a counter trend move a couple of weeks ago. Since then it broke down.
The current very short term trend (within 3 days, and intraday influence) is long.
Since this is a counter trend move (the short term countering the 3 month) you can make money both sides in intraday active trading.
But if you try to combine trading the 3 month down bias and intraday long, what to do ?
Contrast this with focusing on a single time frame. Then you know better what to do.
the 3 months is short, so considering the current market action, you either take profits or accumulate on the retrace (or both actually, in time).
the shorter time frame is a repeat of the bigger picture most likely : rising wedge again. if you went long you made money (even with very short term trades).
I am not saying you can't look at both time frames. Sure you can. The optimum imho is to trade both time frames but separately. That's what I do at least.
The trouble comes when within one trading strategy you mix up time frames. it can yield bad decisions because of confusion.
Stop loss are mixed up and opposite, etc.
If you are discretionnary, it's even more important to avoid confusion. If your strategy is more mechanical, then the process can be embedded in the rules and more manageable.
as usual, there are many ways to make money. but why not seek simplicity most often ?
tntneo