I don't need any help with blunders, I fill my quota every game all on my own.
Sometimes blunders aren't very obvious until your opponent opens your eyes for you. Sometimes when that happens, it can almost delightfully surprising. To truly understand a position to the best of whatever your abilities might be, time is your best, maybe your only, friend. You must examine every reasonable possibility, and it doesn't hurt to look at some less-reasonable-on-the surface possibilities. . . . and this takes time.
Blitz teaches you nothing and more often than not blunders in blitz games simply stay hidden because your opponent has no more time than you to find and exploit them.
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