Double quotes keep getting less and less effective -- Google is progressively ignoring them more often when similar results are available. Worse, I've seen Google tell me that a term in double quotes simply doesn't exist on the web, when other engines will return many thousands of results. I seriously doubt that the competition has a bigger index!
I have, that's actually why I switched. I was getting better results with DDG.
I think what I've noticed with technical searches is that Google tries too hard to "predict" what I am looking for. It always ends up showing me irrelevant (but surely highly ranked) fluff related to prior searches. The thing is, I don't need to see something related to my prior searches. I need to see what I am looking for TODAY. For me the "personalization" is often actively harmful.
This is what finally put me on using DDG.