No matter how much ever one tries to embrace and love it, grammar of any language always remains a dry subject. At some point of time, the mind wants to stop analyzing and start to take things as-is. Panini's grammar rules, no doubt is a great tribute to human intelligence. At the same time, another extra-ordinary intellect, Adi Shankaracharya asks "What is the point of studying grammar, when the real liberation is achieved only by chanting the name of Govinda".
Chanting the names of Vishnu is a sure way to moksha especially in Kali yuga - Vyasa emphasises this in several of his works. The more you call his name the more the chances of liberation. So, of what use is memorizing and repeating the undecipherable technical terms of Panini - most of which does not even sound like a proper word, when the mind can be repeating the thousand names of Paramatma? Do the words like ShtunoShtu:, k~giti ca, ikoyanachi get a person any closer to moksha?
Thus the bhakta is at cross-roads with jnana. Should one study the intricacies of grammar or just chant the names of mAdhava? And why can't he do both?
A variety of literature has followed AshtadhyayI. While the SutrapATha (AshtadhyAyI) remains the ultimate focus of these literature, the literature itself spans several dimensions - vritti (gloss), vArtika (notes), bhAshya (exposition), siddhAnta (theory). Sutra was extremely concise, so vritti was written to supply missing elements. vArtika expanded the sutra, while mahAbhAshya was an extensive treatment, leaving no gaps. Kasika vritti, siddhantakaumudi, laghu siddhanta kaumudi have treated AshtadhyAyI extensively. In between there are novel attempts like BhattikAvya which attempts to teach Paninian grammar via Ramayana.
In the juggernaut of the Bhakti movement started around early 8th century (?) with Azhwars/Nayanmars and gained prominence throughout India by 15th century, someone snaps, why do I have to read all these grammar rules while I can be chanting the name of Hari? Of what use is this grammar when nitya sukham is in repeating the names of Krishna! And thus Jiva Gosvamin creates a brilliant work - 'Harinamamruta vyAkaraNam' - literally "The Grammar of Nectar of Names of Hari". It is based on Panini's grammatical rules, but every technical term is replaced by a meaningful facet of Vishnu.
Let us look at some of the parallels of Panini's technical terms and Harinamamruta vyakarana
vowels/varna/svara (ac) - sarveSvara:
first 10 vowels (ak) - daSAvatAra
each pair of vowel (hRsva and dIrgha) - ekAtmaka
hrsva - vAmana
dIrgha - trivikrama
pluta - mahApurusha
anusvara - vishnuchakra
anunAsika - vishnuchApa
visarga - vishnusarga
ka ca Ta ta pa - hari-kamalam
kha Cha Tha tha pha - hari-khadga:
ga ja da Da ba - hari-gada
Gha Jha dha Dha bha - hari-ghosha:
Adesha - virinci
Agama - vishnu
pumlinga - purushottama
strIlinga - lakshmI
napumsalinga - brahmajna
avyaya - alinga
lopa: - hara:
and so on. All the technical terms are carefully replaced by equivalent meaningful facets of Vishnu! Thus Jiva Gosvamin creates about 3192 sutras - a devotional parallel to Panini's AshtadhyAyI.
The intellectual devotee fulfils two purposes immediately - learn grammar by chanting the names of Vishnu. Talk about direct ascendency to moksha by bhakti through jnana!