I meant to add:
A good indication of this is when studying your bottom line results log. By that, I mean once you've been trading for a while & attain an acceptable level of consistancy, you'll notice a pattern appearing.
The win-loss ratios, peak to valley drawdowns, total % profits & typical positive set up expectancies should be pretty close to an avg line.
Taking out irregular market behaviour (which will
skew short term results), the 12mth accounts should be pretty much balanced.
A good % of this consistancy can be attributed to a traders psychological maturity & symmetry with their normal plan-structure model.
And again, this type of behaviour will be due in part to the instincts gleaned by familiarity with the chosen instrument/candidate.
Well, that's my take anyhow!