It was devised following Jules Bianchi's tragic crash. Personally, I think it's quite a good idea as some incidents don't require a full safety car and yet need more control than simply locally waved yellows. Given the terminal velocities of these machines coupled with the red-mist racin' rage of the pilots it seems another layer of safety was needed.
I actually think it should keep the race flowing better, but ironically, it was the difference between the speed delta of the VSC and the deployment of the actual SC that proved Lewis's undoing, never mind the doubtful wisdom of changing tyres. If the VSC had been left in place - he would have got out ahead.
But that's F1!
PS. Re: Lewis's attitude afterwards. If you exclude parking at the tunnel and crashing into the 3rd place marker then yes, I suppose he was professional. He should be, it was a 50% call and he was the man on the spot. To be honest, I think he asks the team far too much and then tends to cut them off when they give him info. I think he should trust his gut more...