Unless something I don't know about has changed (which is possible, since I grounded myself about 10 years ago), it's not "regulated airspace." It is a narrow, VFR, see-and-avoid corridor under and through regulated airspace
I appreciate what you are saying stepwilk, and a warm howdy to you to, is that the traffic in the corridor is not actively "controlled".
What I am saying tho' is that it is "regulated" that the traffic "has" to fly within "the" corridor, therefore it is regulated to do so, and dangerous as proven, as are airport traffic procedures at non controlled airports for fast and slow aircraft conflict.
Another such corridor is the VFR route across the middle of LAX, Now that's a right spooky place, unless rules have changed.
A small ob on the way past is that a Lance, Saratoga or whatever once established in EOL mode will be flying at a slower IAS than the discussed helicopter in cruise mode.
We have a CAO here where VFR helicopters are "allowed" to depart non standard procedures and ask for same at controlled airports. In my mind it would be so refreshing to see that procedure described with a far higher degree of imperitive, you know "you will if possible" rather than 'you may'.
It's something that the safety foundations 'could' or more correctly, to follow my logic, "should ' zero in on.
cheers tet