Knobby,
Agree with what you're saying in some cases - but it all depends on the circumstances. It certainly wouldn't be appropriate for an instrument approach, for example. And in the case of Welshpool which Whirly described, if it was a pilot's first time at the airport he might not know about the windshear until he encounters it (or even if he's been told about it he has no way of knowing how strong it is) which would make it difficult to compensate for in advance
FFF
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