I think breakthrough is sort of considered a "heroic dose", that being 5 dried grams or more.( Terrance preached this all the time and also how you can hear the entities but don't see them and more auditory hallucinating..,he mentions a hard headed man said this never happened to him, then he pushed the dose up to I think he said 8 or 10 grams and found all that McKenna had been speaking of).
I personally have had MANY 5g trips with Cubensis and every time it is a wonderful experience where I am still somewhat coherent no matter how heavy the visuals become..I love OEV but I feel that CEV have a much bigger message and BETTER chances of having a crazy trip and then witnessing "something" (mine would be a quarter ounce, 7g of very potent mushrooms probably some Pans or something on the stronger spectrum with cubes..I had no choice but to hit the bed and basically just flooded by visuals(toward the end of this peak is when I realized innate primal animal characteristicts, like I am MAN, flesh with a soul, or something..and although I do not recall ALL CEV, I did see my room had changed greatly when the peak was fading when i opened my eyes again(any time before this I couldnot distinguishif eyes were open or closed), a BIG giant human sized mushroom in the corner of my room which then morphed into a samurai like warrior with a big hat facing down could not see eyes, this did not last long.
After eating a few ounces of Pans (I never ate more than an eighth as I am new to these). I realized I loved the beautiful colorful hallucinations but it seems to be lacking the spiritual teaching aspect part...more of light show, which one could argue that a colorful jellyfish look-a-like passing by as an entity that they observe.
In fact after reading Doors of Perception, it appears these spiritual experiences or a visual dream like experiences are in a sense, "breaking through", in my definition.
"Men have attached more importance to the inscape, than to objective existents, have felt that what they saw with their eyes shut possessed a spiritually higher significance than what they saw with eyes open. The reason? Familiarity breeds contempt.." Doors of Perception including Heaven & Hell - by Aldous Huxley
I try not to get stuck on the entity part too much as YES this was the first time a heroic dose pushed me the furthest, the rebirth trip, the event that I will always recall...
LSD brought me to 3 different other (dream states) entities but also it was CEV and a visionary experience that hit in the sense of a dream..because I was transported, so to speak, to this geometric room/landscape and then praying mantis doing something to me, that felt right, like I was being healed or prepared for something. I have been unable to go back to these states no matter how hard I try, I think the key is of course abstinence and then dosing for reasons of healing.
Sorry if it seems like I am rambling but I feel if you have tried 5 grams dried a couple times, push the envelope and try 6.5 or 7g. It's a bit overkill(and trust me you don't want to "blackout and miss it all" so try to find your sweet spot.) For me 6-8grams of cubes.. 3.5g of Pans Cyans is a similar nervousness before the trip as a 5g cubensis may make me..other times I am fearless.
Interesting topic and love this discussion..I love LSD for transporting me to these visual experiences that were MUCH further and beyond watching tracers or wood grain.. I feel that if you have not experienced 5grams or more, you need to. Your first trip I'm sure was miraculous no matter what strain or even dose, but I always tell people 3.5grams is what mushrooms are all about and 5g is where you really start to transcend into unknown territory that is usually fascinating in every way.. I love LSD but somehow falls short of CEV for me somehow, it is strange but I feel it is partly why McKenna was an advocate for plant medicine as mushrooms do indeed make you hallucinate furiously.
Sorry if this is hard to read/confusing my apologies, I wrote this up pretty quick.