Removing leaves

The leaves on my tomato plants are quite large this year, so they are shading a number of my tomatoes, so should I remove some leaves, half the size of them or just let them grow,

I hedge my bets and remove some in total that are shading later on in the year but say halve them early on, I look at how big the plant is and judge (rightly or wronly) whether it will suffer by being shorn. Not saying that's the right way though. I have the same dilemma with taking off the lower leaves.

I take off the yellowing or sickly leaves - anything green is left to be seen.

I take any leaves off below the first truss and any leaves that are covering trusses.

I take off up to the first truss and reduce the size of any monsters further up. With the prevalence of blight, my plants can finish the year with just one or two sets of leaves!