I'm not sure of the laws in the UK but here in New Zealand hims can marry hims and hers can marry hers.
I am not debating the rights and wrongs but am concerned at the genealogy problems that will ensue in the future.
It has its difficulties now as the shes change their surname to their husbands (most, anyway) but the tracing of the ancestry through two hes and no shes will make things difficult. It is a system that has worked for a long time but now will be chaotic. For instance whose name do the children have , yes these people have children, and if double barreled in the future will they treble and quadruple them.
Even the two partners, do they retain their own surnames or take their partners. Either way, what will the records show? If two male names then which is which? Perhaps a glorious data base of DNA will sort things out.
I sure would not like the job. Can anyone simplify this for me.