As everyone else has said, this is a risky practice due to heat-tolerant bacterial toxins. Here is an article about it, if you want to do some more reading:
https://blog.foodsafety.ca/what-are-bacterial-toxins
The reason the meat smells better after you partially cook it is that you are killing the spoilage bacteria coating the outer surface and washing away or destroying their smelly byproducts. Oddly enough, those aren't the really dangerous bacteria. The ones that cause serious food poisoning mostly do not stink.
Also, cutting the larger chunk of meat up into smaller pieces is a very bad idea. You are just spreading the surface contamination into the muscle. Also, using water as a medium actually limits the upper temperature you can achieve. If you really want to save a piece of meat while minimizing your risk, do this instead:
- Leave the cut of meat intact.
- Put a high-heat vegetable oil like canola or sunflower oil into a steel frying pan.
- Heat it until the oil smokes just a little. The smoke point of sunflower oil is 248 Celsius, whereas water boils at 100 Celsius, so you can easily see why this method is more effective than boiling.
- Pick up the piece of meat with two pairs of tongs and place it into the hot pan. Rotate it around until a brown crust forms on the outside. This is called searing.
- Remove the meat from the pan and let it cool.
- With a clean sharp knife, cut off the seared meat at the surface and discard.
Note that you should not attempt this with poultry, only whole, non-tenderized cuts of beef or pork. This, by the way, is how restaurants prepare beef for serving raw dishes like steak tartar. Or at least that's how they are supposed to prepare it from a food safety perspective.
Note also that this doesn't guarantee that the meat is safe, but raw, whole, non-tenderized cuts of meat are usually only contaminated on the outer surface. Obviously it is safer to avoid the risk altogether, but if you must try to save the meat, this method is far, far better than your current practice.