Could you elaborate on what it means that a letter has strong/weak reliance on its' articulation point?

Question
Assalamu 'alaikum wa rahmatullahi wa barakatuh
 
In shaa Allah you are all well and in the best of eemaan and health, ameen.
 
Could you elaborate on what it means that a letter has strong/weak reliance on its' articulation point? The letters of ash shiddah are stated as having complete reliance on the articulation point. What is the difference between strong, weak and complete?
 

The way I understand it, (without any source of reference) is that it is just something that is a natural occurrence and letters have differing amounts of dependency on their respective makhaarij. What this means in practical terms (which is what students want to know) would be that with some letters it is possible to not hit the makhraj 100% without making an error (or significant error) in pronunciation whereas other letters end up being mispronounced if the makhraj isn't hit properly - hence differing amounts of reliance.


Jazakumullahu khairan kathiran
 
Wassalamu 'alaikum wa rahmatullahi wa barakatuh

Answer
Wa alaikum assalaam wa rahmatullahi wa barakatuh,
First of all, we apologize to you and all who are waiting for an answer to their question or questions and there has been a delay in the answer.  May Allah give us barakah in our time and purity of intention in all we do. 
Jazakum Allahu khairan, we are well, al-hamdu lilla and ask Allah to increase us and you in faith every day of our life, and that we meet Him and He is pleased with us.

A strong reliance on the articulation point means that the articulation point is closed off wehn the two parts of articulation meet,  There is a strong pressure one feels at the articulation point when closing it off, ie strongly relying on it, for the letters of shiddah.  The letterfor example, the middle part of the tongue and the roof of the mouth which opposes that part of the tongue are closed off; therefore sound cannot pass through the articulation point and there is no continuous flow of sound.  One cannot prolong the sound, even if they wish to if they are pronouncing the letter correctly and closing off the articulation point.  The letters of shiddah all have a closed articulation points when pronounced properly.   Mistakes can happen, so although it should be a natural occurrence in theory, it is not always a reality, even for Arabs.  It does not mean that the student necessarily has an improper articulation point.
With our example of the letter , if the articulation point is not closed off, the sound will run through it  obtaining then the characteristic of rikhaawah, and the resultant sound is one that many colloquial Arab dialects have for this letter, but not the proper true correct   required in the recitation of the Qur'an.   The two letters and the share the same articulation point with the , but both of these two letters have rikhaawah, or running of the sound.  There is not as much pressure on the articulation point (weak reliance) meaning it is not closed off, so the sound runs through when pronouncing these other two letters.   You may feel this if you say a saakinah and feel the middle of the tongue not completely closing off the roof of the mouth which lies opposite, then say the  saakinah; if pronounced correctly, you will feel a strong pressure as the middle of the tongue and the opposing area of the roof of the mouth are closed off. 

A complete reliance on the articulation point is seen in all the letters of shiddah which also have jahr.  A strong reliance is in the letters which have a mixture of strong and weak characteristics, such as shiddah and hams, a weak reliance on the articulation point is seen in the letters that have both rikhaawah and hams.  The air flowing in hams means that the articulation point is not closed off, so it has a weaker reliance than the letters of jahr. 

Insha' Allah this helps explain it.  If you have an further questions, feel free to ask us.   Insha' Allah we will be more prompt in answering.
Wa iyyaakum.
Wa assalaam alaikum wa rahmatullahi wa barkatuh.