Horsepower
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However, what I’m really asking is whether or not an aircraft should be deliberately flown through a warning, especially at such low level and low speed </font>
If that is the question you are asking, then the answer is as before - ignore the warning. That warning is not intended for the circumstances you describe, but rather for the poor soul about to land gear up. Presumably that is not a real risk in the circumstances you describe.
Get the gear up once you have a positive rate of climb, and no possibility of landing ahead. Once those conditions are met, and assuming you are at a safe flying speed (negating the earlier point about the drag of gear in transit), get them up and out of the way ASAP.
-2Donkeys