In the description of the industrious endeavors of the locals in India recycling various components, it would seem that such crafting would be reduced to mindless commercialism.
It seems in the weaponry of India, there are all manner of examples that elude comprehension of thier practical use, many with multiple blades, odd shapes, bizarre features and so on. Without deeper understanding of the traditional features and often symbolism of weapons associated with ceremonial events as well as martial applications, it is often difficult to transliterate functionality into western perspective.
This dagger is, as agreed, a married piece, using a sword hilt that would seem incongruous to the traditional means of using a dagger, however Davids suggestion (using the western term main gauche descriptively) would seem to indicate possible imitation of western swordsmanship. Although we know that as the Portuguese presence in Malabar became emplaced, thier weapons influenced the Indian forms markedly. The baskethilt developed, mounted as 'firangi' with foreign blades, and as we know, many were the narrow rapier blades. It does not seem too far fetched that the European fencing styles were in varying degree imitated, and use of the main gauche technique quite lilkely observed.
As always, my lack of martial arts knowledge being clear, it does seem that European fencing used the sword and buckler as well as the sword and main gauche, with both used in parrying blows or thrusts. With the rapier of course, the thrust parry involved the use of the main gauche to catch the opponents blade. A well protected guard for the hand would seem quite advisable, though in reality the unsharpened rapier edge was not really a threat to the hand.
Lat night I watched briefly a documentary on the martial arts technique of kalaripayattu in Kerala, India, in which opponents armed with sword and buckler engaged in extremely theatrical appearing combat. Much of this was quite choreographed with turns and leaps, which was described derisively by Sir Richard Burton whose views of native Indians was generally less than favorable in this regard. There were later shown some highly costumed and colorful traditional dance ceremonies using some of these techniques. I wonder if similar reeanactments might have also used the left hand dagger in imitation of the European fencing style?
I also found a very interesting entry in Pant (p.174) showing a dagger with very similar blade shape ( the leaf shape also termed 'gojivhagra' =tip of cow tongue, ibid.p.101). The dagger is known as a katar, katara (here Pant notes that the familiar transverse grip weapon is properly termed 'jemadhar) and the profile seems very similar to this piece. Obviously the full baskethilt does not concur with the hilt on this illustration, but the similarity seemed worthy of note.
Although it is clear that in India, among many spheres of culture, there is an industry fabricating all manner of souveniers for the thriving tourist industry. However it is important to remember that in many cultures, traditional weaponry is still an important element of costume. In other cases, there are votive pieces that are used in religious and traditional ceremonies as well. While these typically would not serve as functional combat weapons, they are typically representative of traditional and historic forms, in varying degree of course.
I guess all this simply means to me is that despite the relatively infallible quacking theory, it always seems worthwhile to keep an open mind
Besides, the search for the obscure against the odds is part of the fun!