In Al Ahad we can see that the letter was connected to Dal from the bottom of Dal. So did in Al Hayyu and As Sobur where the leter Ha was connected to Ya from the bottom of Ya and Ba was connected to Wau from the bottom of Wau .
From this type of letter connection, we can see that the connected leter stand as isolated form. I have discused about this issue in my previous entry here.
This is a proof that square kufic doesn't solely create its own rules. There are also references made to other type of khat. However, there are condition where and when to apply this references. The most important is the letter was given its right in term of character and method of connecting.
Some square kufic activist emphasised that they strictly follow the 'arabic/ jawi script'. This make them produce square kufic based on true connection of 'arabic or jawi script'. However, in some cases they found dead end and they create the problem solving by compromising the right of the letters. For instant, the letter with dots below it (eg. Ya and Ba) and letters with dots above (eg. Pa and Nga) was not given their right where the dots were placed outside of the letter.
My observation conclude that they actually do not understand what they meant by saying that they were strictly follow the 'arabic/jawi' script. The script is a matter of font. But if they meant by following the 'arabic/jawi' script in term of letters connecting, they should be firm to what kind of khat they were referring to. Is it nasakh, tuluth, riqaah or what?
In Arabic/jawi script, the letter conncection is important because whithout connecting the letters, it won't build up a word. For eg. if you write Ya Wau Mim separately, they were just letters. But when you connect the three letters together, it will read "Yaum" in Arabic which mean "Day"
As square kufic is a kind of monumental calligraphy which mean they were originally made on wall rather than on paper, the method of connecting square kufic letters were made based on materials used. However, they have their own rules and they also refer to other khat in some cases.