@Mangan150 So hang on. The TG quartiles have decreasing HDL ie the higher their TG the lower their HDL.
When you correct for reduced HDL the TG effect basically disappears.
And a low denominator (HDL) results in a high TG/HDL ratio.
So the culprit here isn't high TG, it's low HDL.
An inverted curve isn't a technical indicator like a moving average. Rather, it has real world implications. If you borrow short to lend long, your profit margin is gone.