As Dena said, and I'll paraphrase, it's the rate of change that defines the effects of "low" vs. "high". And rate of change is proportional to dosage over time. The final extent of change (where you end up) depends on lot's of individual variables, i.e. genetics and family history, age, health, co-morbidities, diet, etc. As with any pharmaceutical, it's all about the dose. The standardized (haha, really?) doses for HRT that we read about and that are administered are starting points.
Here's a for instance: I'm on what would be considered the starting doses of Spiro and Estradiol (oral). My first blood test came in after 3 months. The T was a little bit high by cis-female standards and the E in the lower range but still above the minimum. I'm feeling and seeing some slow change and I'm happy. The boobs are sore (slightly fuller but not measurably larger), the body hair growth slower, softer skin, etc. Most importantly for me my dysphoria is much quieter. Now that's subjective, I know, but both my partner and my therapist have independently noticed that I am much more chill now. My doc asked if I would like to have the dose doubled since I'm not in the center of the female range. My answer was no. I'm good for now. Not being out or socially transitioned, this is a good low dose place. If I get dissatisfied with the rate of change, I can bump up the dose. On the other hand if things start to move faster than I am ready for, I can titrate back (lower) the dose. My therapist says all the time: you are in control of your transition. And yes, if you are on HRT, make no mistake, you are in transition but how that happens is up to you. You may, like me choose the slowest rate which is virtually unnoticeable externally to most people or go for it.
I can even change the effects myself over time, not by changing the official dose but by changing the way I take my meds. I currently take the Spiro on an empty stomach in the morning. I can make it more effective by taking it with a meal instead (that'll bring the T down a little more), since Spiro is better absorbed and has better efficacy when taken with food. If I eat some grapefruit or drink the juice during the day it'll bump the E over time since a chemical in it inhibits the metabolization of E thus keeping it circulating in the body longer (well documented). In the other direction, I could skip a dose every so many days to lower the averages.

I think one needs to consider, that these "normal doses" are only suggestions based on average dosing requirements to achieve MtF transition in a timely manner.
Most MtF transsexual hormonal dosing guidelines I've read, assume the patient want's to transition ASAP (to end the gender dysphoria as fast as possible, presumably). There is no consideration of the patient's personal or professional life, nor the results she wishes to achieve. 

That being said, everyone's hormonal baseline is different. This is often affected by genetics, health and gonadal development. For example, my baseline Testosterone was at 1310 ng/dL ("normal" male scale is 300-1100). Therefore I have to take a higher (than recommended) dose of T blockers to get my levels in the female range.

My friend who is also a transitioning MtF, only takes Estrogen. Due to her pubescent development, her T is already low and doesn't need any T blockers.

Also, hormone levels can change, especially after testicles begin to atrophy (get smaller).

This is why it's NOT recommended to self medicate without the supervision of a medical professional that can order blood tests to monitor hormonal and non-hormonal levels.

I was on the lower end of what is generally considered a transition dose and results occurred for me immediately. I have since increased it twice.

It sounds like what she's actually saying is that you need to be prepared for transition and major changes *even if* you take a typically low dose, which is really pretty accurate.

I started on a super low dose (less than half of the bottom of the range for what is generally recommended) with no anti-androgen, and I ended up a C cup within three months and outed at work by the changes within four months. It's uncommon, but you do need to be braced for the possibility that any dose will have that sort of consequences.

Quote from: rachel.i. on May 15, 2017, 08:50:55 PM
So, is low dose real or is it something made up by the people that self medicate?

Does anyone have a website I can give the doctor for in site into what it is?

If low dose is a myth then I'm a unicorn!

Never self medicated, even though I was sorely tempted at one point.  Basically dosage at a level so that feminisation rate is very slow or negligible as far as physical is concerned.   On the other hand, the emotional effects are quite significant- especially being a lot more labile (i.e. I'm more laid back and also get teary a lot more easily)

It's been 5 years and counting and I'm yet to transition socially.