Well, you could at least refute my rationale, question it, or support it? Else, it might be reasonable for me to assume that that it is YOU that is being argumentative debating!
No, it would be very /unreasonable/ for you to make that assumption, since silence cannot reasonably be interpreted as argument. Lance Armstrong has decided to no longer contest the allegations that he took prohibited substances while a professional cyclist; this decision cannot in any way be interpreted as argument, but can (depending both on one's own point of view and on one's open-mindedness) be interpreted either as a tacit admission of guilt or as a refusal to waste any more of his life on rebutting accusations that he knows are baseless but which he can nonetheless not disprove.
if we were to discuss BIR cuisine and only BIR cuisine, then I for one would find this forum a poorer and less interesting place to visit
But, surely, that's the main theme of this forum?
I agree, it is the main theme, and the theme that unites us all. But just as in any population united by a single theme (e.g., all Britons) there will be sub-populations with specialised interests that are not of interest to the main population at all (e.g., supporters of "Friends of the Earth"). So long as the minority interest debates do not swamp the forum, then all can benefit, because the forum will be perceived as open and welcoming; if all off-topic debate were stamped upon by an over-zealous moderator, then (IMHO) most would up and leave, perceiving the forum as a sterile, barren desert in which all debate other that along strict party lines will be stifled.
Surely, the rest is simply mindless banter for mindless people that have nothing better to do?
"Mindless" banter ? I think not. The debate on ground coffee v. instant coffee was anything by mindless, as are many other non-BIR debates that take place here (I would add the debate on wine snobbery and wine names to that list, for a start). Chicken sizes started as a serious question : "where /are/ chickens pre-classified as being of a given numeric size ?", and because one member made a humorous reply, a further humorous reply followed. If chicken sizing took over the forum, and we debated nothing else, then you would most certainly have grounds for complaint; but a brief light-hearted diversion is, IMHO, a good thing now and then.
For me, I would rather this forum focused on cooking BIR curries (preferably those pre 1990).
In my experience (quite a long one, even if not quite as long as yours), BIR curries are exactly what it focusses on. And pre-90's curries get their fair share of attention, even if such debate does effectively exclude any member under the age of about 40.
But, since Admin doesn't even use a curry base...what are the chances, really? :-X
/Ad hominem/ attacks invariably reflect more poorly on those making the accusation than on the individual named.
I am still looking for simple answers, to simple questions, that I asked years ago...and those answers are, sadly, not forthcoming.....and fine cigars, fine wines and ladies' bra sizes were certainly not the nature of my questions! 
In general, presenting the members of any forum with a whole slew of questions is rarely likely to result in any worthwhile debate; few of us would have either the time or the inclination to debate such a list. But if you were to ask a single, focussed, question (e.g., "at what point in the evolution of BIR cuisine did Patak's products start to play a major role"), then the question -- being finite -- would immediately attract interest, and lively debate would ensue.
My EUR 0,02.
** Phil.