"Clostridium botulinum"
Has absolutely no bearing on the equasion at all.
Botulism bacterium are anerobic. They won't propagate on the surface of meat.
It's a non-entity in this scenario.
Camplyobacter and salmonella, however, are.
From the US Dept. of Agriculture
"Safe Defrosting
There are three safe ways to defrost beef: in the refrigerator, in cold water, and in the microwave. Never defrost on the counter or in other locations.
Refrigerator:. It's best to plan ahead for slow, safe thawing in the refrigerator. Ground beef, stew meat, and steaks may defrost within a day. Bone-in parts and whole roasts may take 2 days or longer. Once the raw beef defrosts, it will be safe in the refrigerator for 3 to 5 days before cooking. During this time, if you decide not to use the beef, you can safely refreeze it without cooking it first.
Cold Water:. To defrost beef in cold water, do not remove packaging. Be sure the package is airtight or put it into a leakproof bag. Submerge the beef in cold water, changing the water every 30 minutes so that it continues to thaw. Small packages of beef may defrost in an hour or less; a 3- to 4-pound roast may take 2 to 3 hours.
Microwave:. When microwave defrosting beef, plan to cook it immediately after thawing because some areas of the food may become warm and begin to cook during microwaving. Holding partially-cooked food is not recommended because any bacteria present wouldn't have been destroyed.
Foods defrosted in the microwave or by the cold water method should be cooked before refreezing because they may have been held at temperatures above 40 °F.
It is safe to cook frozen beef in the oven, on the stove, or grill without defrosting it first; the cooking time may be about 50% longer. Do not cook frozen beef in a slow cooker."
The guidelines for poultry are identical.
From Cook's Thesaurus: " Warm water method: Immerse the frozen food in warm water or run warm water over it. This is a good way to thaw frozen juice cans, but dont thaw meat or fish this way."
From the Wisconsin Beef Council
"Never defrost meat, poultry or fish on the kitchen counter or in warm water. Bacteria multiply rapidly at temperatures 40° - 140°F."
From Hormel Foods
"Do not use warm or hot water, even though it will thaw the pork faster because it will also encourage the growth of bacteria."
National Center for Home Food Preservation
"Never thaw food at room temperature or in warm water. Even though the center of a package may still be frozen as it thaws on the counter or in the warm water, the outer layer of the food is in the "Danger Zone," between 40 and 140°F. These are temperatures where bacteria multiply rapidly."
A whole series of on-point references from the CDC:
http://www.cdc.gov/search.do?action=search&queryText=defrost+meatAnd so for and so on for over 350,000 similar hits on the web.
Today's cooking methods, in which rare and medium rare meats are ever more popular, are no guarantee of eradicating bacteria from meat once it has begun its turn to the dark side.
I'll say it again.
NEVER defrost meat in a warm water bath.
If YOU want to do it, be my guest. Just recognize that you're greatly increasing your liklihood of taking an extended porcelain vacation.
