1) Thaat system as is well-known, was created / established by Pt. Bhatkhande ji.
It has been acknowledged that Pt. Bhatkhande ji contributed greatly to the cause of
Indian Music through his collective efforts to standardize both the content and
nomenclature of different prevailing ragas.
In my opinion, thaat system is essentially meant for a general understanding of
categorisation of ragas divided into 10 thaats. However there are exceptions. There
could be some examples of fitting ragas like Madhuwanti in one of the thaats.
I recollect very well that in olden days a sarangi player would ask the main vocalist ‘in
which thaat should I tune my instrument’. This implies that prevalent definition of a
thaat was related to the scale of a raga.
To conclude, I would recommend that it is good to know details about the thaat system
and the classification of the ragas according to the same. However, the focus should
be on individual ragas – and individual ragas only and not the thaat to which the
concerned raga belongs according to Bhatkhande ji’s classification.
2) Vadi / samvadi concept : whilst this concept may be of some value to the
students of music. It is useful to know the basis, to start with. However, my
assessment is that whilst a musician is developing a raga – especially in the alap, he
does not give greater importance or emphasis to the vadi note of the concerned raga
as compared to samvadi note. Some of the musicians are not bothered about thaat
that the raga belongs to, they just develop the raga according to their Talim.
Such a Talim that I referred to, translates itself into resting on significant notes whilst
developing a raga. Ustads used to call such notes as ठहरनेकी जगह . I would like to
call them melodic centres. Each centre has its own value, neither lesser nor greater
than the other. There could be more than 2 centres in raga like Yaman, where we
have Gandhar, Pancham and Nishad as resting points (ठहरनेकी जगह) or melodic
centres.
3) Arohi / Avrohi : as explained earlier, the concept of arohi / avrohi is essentially
meant for students of music. Just as the chaste language, over a period, changes
itself in to a colloquial language, though also arohi / avrohi concepts changes into what
we call challan. Not only that challan partially simplifies the concept of arohi / avrohi
but is used by musicians to have calculated freedom from the strict tenets of arohi /
avrohi concepts. In my opinion, musicians who follow arohi /avrohi strictly would be
called ‘kitabi gavaye (musicians)’