I ride primarily in town, so my unclipping anxieties are more about sudden cutoffs by cars rather than skinnies (whatever they may be) or tree branches. however, as someone said above, unclipping quickly has become a reflex action now, so no longer seems a problem, even in a panic stop. BTW...I have my SPDs on their loosest setting...seem to work best for me there, can get out fast, but have never had an unwanted release.
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