I think its a combination of things. I don't think that Williams really planned on having to blitz as much as he is seemingly now forced to. But I also think he (and the entire defense) is frustrated that they haven't been able to generate the kinds of results from the front four as they imagined they would. I mentioned the lack of sacks this year was a real possibility because teams were so concerned about the pass rush they have game planned an attack to get the ball out quick. And it now seems to be effecting how the Rams try to counter it.
I am not trying to say that Williams wasn't going to blitz, but I do think he fully expected NOT to have to do it as much as he is.
I also think that our safeties have been given way too much leeway in "free lancing" and more often than not, McLeod end up jumping a route and taking himself out of the deep coverage he is responsible for. It's happened far too often to be a coincidence. If you see him on the TD to LLoyd, he was no where to be found is what apparently was supposed to be a Cover 3 call. He was jumping an underneath route. When your MLB gets a deeper drop than your FS, you've got problems.