[Marcello]

"No it doesn't."

Ok, let's see if I get this.You are proposing to create obstacles on the roads and in order to prevent said obstacles to be easily bypassed you are proposing digging trenches

"to block trucks driving around blocked roads"

Right?

Now, it seems pretty evident to me that this requires a a trench long, deep and wide enough that either going off road and driving around it or filling it to create a passage would be a significant nuisance and time wasting, thus creating a bottleneck. A ten meters long trench simply will not do the trick.
The little problem is that this might require a significant amount of time with commercial equipment. And time is a commodity very in short supply in such scenario.
Never mind you need to plan in advance so that unit X knowns that in wartime is going to commandeer two bulldozers from Schmidt & Co to dig a couple of hundreds of meters of trenches on both sides of Autobahn Y at Km Z.
The rest of your post is true,if a little overstated, and at the same time totally irrilevant to the practical solution of the problem described above.
Now:was it actually planned? I have not got any indication that it was.Neither you have told me.
Yourself quoted the use of nuclear demolition mines:if conventional demolition was so quick and effective as you make it to be why bother with them?
Finally when the problem was keeping columns bottled on roads minefields were the standard solution AFAIK. Not digging trenches. Laying mines is much faster and simpler.

"It is much, much easier to demolish and block than it is to clear and circumvent."

It depends exactly on what sort of blocks are being talked about.The israelis spent a couple of years building the
Bar-Lev line. The egyptians breached it in matter of hours.