In our local club when someone sits down with me for a 5-min game and it becomes evident he/she isn't ready for blitz, I suggest we move to 15-min with stops to discuss critical errors and themes. I think speed play is an important tournament skill for when you find yourself in time trouble, but it's of no value when trying to improve understanding of the game.
When I play someone who isn't ready for 5 min chess, I open with the scholars mate, then sac my queen for a minor piece. Because of the time control, they can't display the technique to win. This lets them know in a different way that we should try a 15 minute game instead
A bit too rude in person for me, I just do that online.
blitz is where you show off how good the vision and instincts you've developed via slow OTB chess and study really are.
This
[edit: is correct / I agree. Just to clear up any confusion
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