...er, depends what aircraft we're talking about. While I agree that QRH/SOPs require NO config change during windshear recovery, on some planes (ATR for example) the main gear doors are open when the gear is down, hence the extra drag would only come from the operation (opening, then closing) of the nosewheel's two half-gear doors... quite a limited temporary drag increase really, but still let's stick to SOPs!
Cheers
