(14) Even with regards to meat that had already expelled all its blood and tzir, we say that a second salting will cause the blood presently absorbed to be released. The first “there are those who permit” is referring to a case of meat that wasn't salted at all. The “those who forbid” at the beginning rule that salt can only expel its own blood but not blood absorbed from something else.
(15) The reason is that it has nothing to expel, for it has already expelled all its blood. It will only absorb what the next piece releases.
(16) The reason that it is not forbidden is because as it releases its own blood, it will also release whatever it absorbed from the piece that was not salted. This is only if the meat was not washed after salting. However if it was washed off after its salting, then a second salting will not help to release its tzir since its pores are now closed up. This is only if it was washed after the required salting period, however if it was washed before the required salting period we do not say that the pores have been closed, and another salting will suffice. The Rema seems to rule over here that a washing does not close up the pores just as the Tur rules as well, but previously he ruled they did. It seems that if meat that has completed the required salting time fell into meat that is in the process of being salted, it is permitted because of the rule that “as it absorbed, so will it release." As it absorbed from the pieces it fell into, it will release it as it releases its own tzir. However, if it fell into tzir it is forbidden, even if the meat did not finish the process of salting and was in it for the amount of time that is considered as "cooking" to take effect. This is not as the Rashal who permitted the meat if it had not gone through the required salting time and fell into tzir and even remained in it for the length of time of “soaking”, if re-washed and salted. Rather, we follow the opinion that the amount of time to effect “soaking” is considered as “cooking" and another salting will not help.
(17) The “entire day” measurement is actually a printing error. It should say “if it did not soak in it for the prohibition of ‘soaking’ to take effect,” If it did soak for this amount of time than it is forbidden even if it didn’t soak for a whole day. It seems that we are dealing with a case regarding a vessel with holes. For the purposes of halacha, the ruling should be that if it fell into tzir during the salting period but was immersed for less than the soaking’ period, one should re-wash and re-salt it. If not, it is forbidden and there is no way of permitting it. If the meat did conclude the salting period and fell into tzir, it becomes immediately forbidden for it is considered roseiach.
(18) The reason is because it was washed before its first salting. One need not soak the meat in water, simply pouring water over it will suffice. We don’t say that it is like meat that was salted without its primary washing.
(19) Meaning that it fell into tzir after it had already released all of its own tzir. That is, after an entire day, or after being washed off after been salted, or even if it is within twelve hours and is not a case of great loss which is forbidden according to the Rema.
(20) Meaning after it sat the required salting time in a case in which a second salting will not help. For example: when there is no great need or loss. However, in a case where a second salting is permitted it only becomes forbidden if it sat for the 'soaking’ period regarding tzir, which is the time it takes water to boil.