Most know what i mean by these nowadays.
These are great to find possible tops in a bull market, but you still have to be extra careful with 123 highs as these are quite common to see and also can give loads of false signals due to the way elliotts wave works with regards to a correction. for example.. a 123 high formation (wave 2 and 4) these can look like a possible turning point but when you factor in elliotts waves then a wave 2 and 4 is an ideal trading oppurtunity to go long from these set ups and the corrections always come in a form of a 123 high(ABC) so you would look to go long at the bottom of a 123 high as such if your expecting wave 3 or 5 next.
In a strong bull market there will be loads of corrections and the best time to go long will be on an abc correction as such.
Saying that, 123 highs are great after a long bull market as this can also signal the end of a bull market when it comes after a long up move. SO bottom line,, Be extra careful with this signal as it can be interpreted in different ways.
I use 123 highs for short term trading with tight stops, but i prefer the 123 low any day