Marginal gains in sport is entirely a British thing, and they were well ahead of everyone else a decade or so ago. I'm not sure how much has changed but would expect them to still be at the forefront, even if they're not out in front by as much as they were.

I just get the internet. If you know where I can get 1Gb fibre for less than the 35 quid I’m paying, I’d be all over that. 

Because if we accept that Salah will go when his contract expired, the season after next we will need to make up his 30+ goal contributions, plus he’s our only world class player in the forward line. Whereas in midfield we have two players who are world class in Thiago and Fabinho.
  On your other point, If you believe the reports we are actively trying to agree on a new contract for Naby. 

Two of the three players you've just mentioned are perennially injured and 31/32.    Next year they will be 32/33, Milner will be gone, Ox will be gone, Keita will probably be gone too. How can buying a midfielder not be a priority?

I actually think Hendo was world class but he's 32. Two of the things that made him world class have fairly depreciated: athleticism and dynamism. His technical ability has always been okay at best and his vision has been sub-par. His leadership and tactical nous is still irreplaceable and that's why he's still such a fixture for us.   Henderson should be our fourth choice midfielder. We should be buying a starting midfielder.