Bhai Gurdas Jee says,
'Vaheguru Gurmantar Hai, Jap Haoume Koyee' = The Gurmantar (Guru's Mantar, word to be meditated upon) is Vaheguru, by meditating upon it, your ego is erased.
No method of giving Naam is given preference - the only prerequisite is that Panj Pyare infuse it in the initiates (abhilakees) in an Amrit Sanchar in Maharaj's Hazoori. Bhai Sahib Randhir Singh wasn't given Naam by his Panj Pyare via this technique of Panj Pyare putting their hands upon his head, yet he rose spiritually very much. Once the Panj Pyare have given you Naam in your Amrit Sanchar all powers of Naam are infused therein. Some jathe do this parchar as per your query - but if their view is right then the method of given Naam reigns supreme over the actual Naam. In Gurbani you will only find praise of Naam & not any particular techniques.
The people who do this parchar as per your query actually believe that there is a difference in Amrit & Naam given by Panj Pyare but Gurbani says, 'Nanak Amrit Ek Hai, Dooja Amrit Nahe.' Many do fall foul of their parchar & go to their Amrit Sanchars to get 'their' Naam & end up having to re-take full Amrit again as their Panj Pyare don't believe in any other Amrit Sanchars as authentic. After a while people who do this realise they've made a mistake, that they questioned their Guru, their Amrit & their Naam. The technique they give is simple breathing 'Vahe' in & exhaling 'Guru' it is a good technique to use when you cant control your mind, but as you've already taken Amrit you can already meditate like this (in total there are 7 techniques with the breath to meditate on Vaheguru they only ever mention 1). Also some jathe conduct physical hugging after they give such Naam in their Amrit Sanchars, but the question then arises as to why this is done if the Panj Pyare have infused Naam, why the hugging? There is no justification for this hugging technique in Gurmat at all.