I knew this one was brewing for months. When Legal Week got around to its annual table of law firm results, there was always going to be a mind-numbing debate about how to treat the law firms put together with multiple profit centres.

In many ways, the days when UK tables from Legal Week or US tables from The American Lawyer neatly summed up the upper end of the global legal services market have already passed. With more than 1,500 lawyers working for foreign firms in London, the UK-based tables already fail to reflect a substantial element of the domestic market. Yet merely replacing them with global tables or UK-revenue specific figures in isolation doesn't look that practical.

I suspect in the years to come we will have to come up with a method that does capture the particular qualities of the UK market while also reflecting the uniquely international outlook of the firms that compete in the UK. But we're not quite there yet. I also feel that law firms operating on the basis of mergers that use group structures would do well to let the market catch up with the evolution that they in part represent. Heavy-handed attempts to push out global numbers or pretend that they operate exactly the same as single profit centre firms will more likely attract unwanted attention on the differences of their businesses rather than convincing everyone of the seamless beauty of their global platforms.

And I say this despite Legal Week roundly rejecting the claim pushed by some rivals that mergers such as Hogan Lovells, SNR Denton or DLA Piper are merely associations – clearly they are a lot more than that. Yet there is something structurally distinct to their businesses and, to a certain extent, working out how they will perform is a guessing game. For all the protestations of managing partners at these firms that it makes no difference, there isn't enough experience yet to tell.

The tone of responses to this week's Big Question does speak of the ambiguity of the structure. There is little feeling that clients will lack confidence in such verein-backed firms or that service levels will be negatively impacted – a feeling that obviously bodes very well for the Hogan Lovells and DLA Pipers of this world. Yet there is a justifiable feeling that such arrangements will be less satisfactory in delivering strategic direction and aligning a single partnership.

And managing partners claiming that such tensions matter for nothing are pushing their luck – it's one thing to argue that the pros of a multiple-profit centre merger outweigh the cons of immediate integration; it's another to pretend there are none.

Beyond that, it's already becoming apparent that there are considerable differences in governance and structure between law firms using broadly comparable models, with Hogan Lovells in particular pushing hard to achieve genuine integration. With no easy answer, we'll have to do our best.