Unless you only play with your favorites, you're going to have EH dates now and then. There is no sure thing.  

I'm a long time hobbyist who, when screening a new possibility, takes a long time to vet her out. I have about 20 rules of the hobby that I live by religiously, number one being the lady absolutely must have great reviews. And yet, nothing is foolproof. While my odds have increased significantly over the old days, I still have EH sessions sometimes. In fact, I had two no shows last year from highly rated ladies.  

When an EH happens, I always go running back to favorites. But as we all know, this hobby is so elusive, favorites are gone before you know it, and we're forced into meeting new ladies. EH dates are inevitable Mr. Cadillac man.

You just can't know who you'll have chemistry with.  
Just like dating in the "real" world.  
There are too many variables to get it to a science.  

It's part of what makes it exciting for me.  

very wise advise once:  There is no such  thing as an expert.

Instead, there are people with varying degrees of knowledge and skill.

Each of us has something to teach, and each of us has something to learn.

Try to do a bit of each each day.

So, to answer your question:  none do