A B737-800 CREW; DEPARTING ORD; EXCEEDED THE 270 KT SPD RESTR IMPOSED ON THEIR ACFT DUE TO DEICING OF THE HORIZ STABILIZER.

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BEFORE DEP; IT WAS DETERMINED THAT THE WINGS WOULD HAVE TO BE DEICED DUE TO COLD SOAKING OF THE FUEL DURING THE INBOUND FLT. WE REQUESTED THE DEICER TO USE TYPE 1 FLUID ON THE WINGS ONLY -- EXCLUDING THE HORIZ STABILIZER -- SINCE THERE WAS NO VISIBLE SNOW; ICE; FROST; ETC ON IT. THERE WAS NO PRECIP AT THE TIME AND THE TEMP WAS APPROX 9 DEGS C. THE DEICER SAID HE WOULD NOTIFY US WHEN THE ACFT WAS 'CLEAN;' WHICH WE UNDERSTOOD TO MEAN HE WOULD COMPLY WITH THE CAPT'S REQUEST TO DO THE WINGS ONLY. THE ACFT WAS SUBSEQUENTLY CERTIFIED 'CLEAN' BY THE DEICER; AND WE DEPARTED THE GATE AND THE ARPT. WE DID NOT LIMIT THE ACFT TO 270 KIAS DURING THE DEP ABOVE 10000 FT MSL. WE BELIEVED WE WERE COMPLYING WITH THE NEW RESTR BECAUSE THE NEW GUIDANCE ON DEICING THE B737-800 TELLS US TO LIMIT THE ACFT TO 270 KIAS AFTER 'HORIZ STABILIZER DEICING' WHICH WE THOUGHT HAD NOT BEEN DONE IN THIS INSTANCE. AFTER TALKING TO DISPATCH VIA ACARS; THE CAPT AND THE DISPATCHER CAME TO THE CONCLUSION THAT IF DEICING WAS REQUESTED; EVEN IF ASKED TO DEICE THE WINGS ONLY; THE CERTIFIED DEICER WOULD HAVE DEICED ALL SURFACES INCLUDING THE HORIZ STABILIZER IN ORDER TO DEEM THE ACFT 'CLEAN.' WE IMMEDIATELY SLOWED THE ACFT TO 270 KIAS FOR THE REST OF THE FLT. NO VIBRATION OR ANY OTHER ILL EFFECTS WERE NOTED. SUPPLEMENTAL INFO FROM ACN 545592: DEICER VERIFIED ONLY WINGS WERE DEICED. ON B737; FLT PLAN LIMITS US TO 270 AFTER HORIZ STABILIZER DEICE. SINCE 270 KTS CAN BE VERY LIMITING AT LOWER ALTS; WE TOOK 20 MINS LONGER THAN PLANNED. IT WOULD BE VERY HELPFUL TO REVISE DEICE PROC TO ALLOW WINGS ONLY DEICE FOR COLD SOAKED FUEL FROST FORMATION. PLEASE LET ME KNOW WHAT COMES OF THIS.