If I'm understanding you correctly, you can get across the nearest lane(s) that are not going the direction you want, and to the center left turn lane, but not all the way across because of heavy traffic. So, you use a gap to make it to the center and wait there for traffic to clear in the direction you want to go.
Let's say I'm one of the cars traveling in the lane you want to merge into. I drive defensively, so when I see you coming out of your neighborhood exit, I have no idea if you are a bad driver who has misjudged the situation or you have it under control.
A bad driver would think they can merge or that people will yield and continue all the way across and merge.
A good driver will do as you do and pull into the center and wait with no intention of coming across the center lane until traffic clears.
Let's say I think, "Man, can this guy see the traffic, is he a bad driver, does he think people will let him merge?" This can freak me out or other drivers out and I might sharply apply brakes or make a quick lane change, both of which are dangerous in heavy traffic. How does one know the driver's intention for sure and how one should react or not react?
Also, a bad driver waiting in the center could become impatient and not do a real fine job merging safely. I see the turn signal and I don't know if the car is going to whip out.
Not every situation is exactly like this one and not every driver is as cautious and skilled as you are and I believe that's what makes it hazardous and illegal.
I don't know if that makes sense to you.