Props to bsiren for calling BS.
Props to OP for admitting BS.
Even at your lowest estimated total of 150 over 8 years - you would have to average about 19 pills per year.
This is about 1.5 per month - every month for all 8 years.
Since you likely went through a period of heavy use in the beginning...
you had quite a bit of spacing in there down the line.
There is research to suggest that some humans are less prone to detectable changes in brain function.
To be more specific - there are two main types.
Former users can be given serotonin agents like fenfluramine, piperazines, MDMA, or even high-dose tryptophan.
Both cortisol and prolactin plasma levels are measured at different intervals.
As with MDMA - the prolactin release is an indication of healthy serotonin function.
Many of these studies have shown long-term (1-2.5 yrs) loss of serotnergic function in abstinent users, as measured by prolactin.
But not all former users exhibit a substantial change.
The heavier users normally do - and most studies would define 150 or more as 'heavy' lifetime exposure.
But there are many studies on more moderate users that suggest small or undetectable change.
In SPECT or PET imaging, radio-active ligands show up as glucose is used in the brain.
The protein that removes serotonin for recycling is visible with different ligands.
And sure enough, many current MDMA users exhibit lower levels of SERT expression.
Former users often recover this SERT protein, but some do not (up to 3yrs).
Again - heavier users typically fall into the group that fails to recover SERT in cortical regions.
In both studies, the particpants that show long-term degredation of serotonin suggest true 'neurotoxicity'.
But even more long-term follow up is needed.
To follow these former users for five years or longer, with abstinence assured, is a very challenging study to perform.
Most critics of MDMA studies fail to appreciate the difficulty of 'proving' that toxicity occurs in humans.
A wealth of animal data shows that repeated doses of MDMA causes a 'lasting reorganization of the ascending axonal structure'.
This is not in debate.
MDMA, esp. with repeated dosing, is VERY likely to cause real damage in humans.
But 'damage' is only defined by substandard prolactin response to future use of serotonin agents...or lower SERT expression in cortical regions.
In practical terms, serotonin may be responsible for a number of higher cognitive functions.
Certain 'visceral' feelings may be lost and fall below detection in cognitive tests.
Most regular users experience some change...although the drug still has some effect.
In research, animals pretreated with MDMA exhibit less 'social' effects and more 'motor' effects from MDMA.
This suggests a greater suppression of dopamine in the nigrostriatal pathway.
And some PET studies of former human users agree - DAT expression in the striatum is lower in this region even after 3 years.
Does this mean the user will describe 'loss of magic'?
Some on BL do.
They feel NO euphoria - up to 4 years abstinence in the posts I have read.
Others describe an altered experience that still contains some euphoria.
You should accept the possibility that you actually have 're-wired' part of your most intricate neurotransmitter system.
Lots of data suggests this is the case, but it cannot be known for certain.
By continuing to re-dose and not properly space your rolls, you are increasing your risk of 'loss of magic'.
I cannot recommend controlling your dose enough.
600mg is a VERY high dose.
I have never seen a human given more than 400mg, even in controversial studies.
And some of these higher doses were associated with changes in cerebrovascular activity that lasted months.
Just be more careful.
If you can't feel a 250mg dose enough - you are ALREADY losing magic.