I tend not to agree with anything the orginal poster says, I tend to think he stretchs the truth in most of his posts....bottom line I just don't like him or his wife very much, but let's put that aside for one moment & assume he is 100% accurate in his story telling.
If that's the case than he has every right to be annoyed. The van driver in question should know better, if the lane was as narrow & the load was that over sized & this guy was driving like this in a construction zone than he shouldn't be driving for a living. Construction zones are dangerous places, narrow lanes, lane shifts, uneven pavement & men & women just trying to do there job.
I would think that since nearly every state has all sorts of signs warning of heavy fines in a construction zone that everyoneknows to slow down & take safety into consideration. Sadly if this is true this guy has given us all a bad name. As far as calling safety. I think right now it's hard for them to do anything, if the new QC's are put in fleet than maybe they would have more information to go by & be able to track the history of the van, but i'm not sure. Most likely there isn't much they can do, because how can they know if this really happened with out some type of video proof, even than it could be a difficult case to prove. Any one of us could call safety & say I saw so & so doing this & that, & it could be another driver lieing about that driver because he is spitefull & doesn't like him.
To addresses the speeding isue, I don't think any truck should be able to go over 75 MPH, my trucks are set for 73 MPH & I get guys BLOWING by me all the time. In the orginal posters case, he is over sized & placared the right way he isn't gonna move for any one & i'm, sure he will stay to the far right lane whenever possible. If you a rig carrying an over sized load you stay away, he isn't gonna move any faster than he has too.
In a normal traffic sitaution with a normal load & normal traffic conditions, driving too slow could cause an accident. I'm a frim believer in keeping up with traffic in a safe manor & not holding it up. I've been driving a truck for close to 20 years & i've never been cited for any type of traffic infraction envloving a truck. I've passed hundred of Police Officers on the side of the orad witha rader gun, i'm not speedeing but i'm not crawling either.