I personally see some positive points with Karahi as comapred to Batta.
Firstly, when Deg is prepared and transferred to a Batta; some of the prepared Deg sticks to some parts of the Karahi. That Karahi-part of Deg never accompanies the Deg; which is to be taken to the DARBAR. So, that Karahi-part of Deg will be used in different ways. If ignored, that is disrespect. Birds and animals may like to enjoy it; in India. If used for preparing, other langar items; that will be used; before the actual major part of Deg. If Karahi is cleaned and washed down the drain; that is again disrespect. So, to avoid all these complicacies; it is best to have Deg in Karahi.
Secondly, at very big gatherings and very large amount of DEG preparations; it is not feasible to have so many Sarabloh utensils of that much big size. Moreover, it is always risky to transfer, so much DEG, which is very hot. Khalsa used to be in Jungles; for so many years. Can we imagine, such transfer of DEG, in those situations. This "compulsion of transfer "; is seemingly a recent invention only.
The idea of bringing Deg in Batta (and never in Karahi); basically stems from the feeling that it is not "cultured and good mannered" or "decency" to take the Deg to Darbar; in the Karahi, in which we prepare DEG. Some of us, with such feeling; do give a further argument. They say that, "Do we eat food in the pan, in which we prepare it? If not, why we do so for GURU JI." This argument at its face value is respect of the Guru Sahib. We must respect this feeling of our Gursikh brothers. Recently; my wife prepared the Deg; for a kirtan programme in a house for a small Sangat and broght it in Karahi. A respected Uncle Ji was very much annoyed and did not do the Ardaas for this Deg.----------------------------------I will never dare to speak, my part of argument to that Uncle Ji, face to face.
My submission is that, Respect of Guru Sahib, should not be fashioned in our worldy standards of Dining Table manners and decency. There is lot beyond that. Gurmat respect ethics for Guru Sahib are different, than used for worldly people. We are not as such bothered about, what suits the public view or how the public looks at those parts of MARYADA.
For an example, I take case of SARABLOH. Food prepared in Sarabloh, becomes blackish in color. It is not very nice to look at, for the public at large. The view is not good. Yet, the SARABLOH is great. Similarly Sarabloh Kara; may not shine as much as a Stainless Steel Kara. Yet that dull look of Sarabloh is more beautiful than the bright stainless steel look.
Having said all that, I do respect the uncle Ji for his respect for Guru Sahib, for being so committed on Karahi vs Batta issue.