Ok then bought a house in February that had new CH installed the
previous September (ducted air out, combi in)

Previous owner left a note saying if the water isn't hot enough, close
the tap a bit. We were well aware of this with certain combis.

Anyway the other half is constantly complaining about how the kitchen
tap doesn't run hot enough and the dishes aren't as clean as they used
to be in the last house. I argue with her to close the tap a bit but
have thes inkling in the back of my mind she's right somehow.

On a side note, I don't think it's the water temparature that's
affecting the washing up but the water itself. We only moved a couple
of miles but even a cup of tea isn't what it was like in the old house.

Anyway,

In comparison however, there's an abundance of hot water in the
bathroom and you can open the taps fully without a problem. The shower
is heaven and you have to run the cold too as it comes out so hot. Way
hotter than it would come out of the kitchen taps at that pressure.

I can expect the answer but is this common?