By high yielding do you mean poundage or individual fruits/plant?
I've grown about 4,000 plus Heirlooms, which is not the same as OP since there are many OP's that are not heirloom varieties.
WhenI look at a single variety in my SSE YEarbooks I see different results for that variety, as expected,since there are geographic differences,it depends what the weather was like when a variety was grown,how they were grown,sprawling, staking,caging,container,etc,as well as any amendments used and if so which ones and when and how much.What is the soil like or artificial mix you use if you do,etc.
All to say that there are many many variables, so if someone says variety X is always high yielding for me where I grow,what does that reall ymean.
As for me,my first priority in growing heirlooms is TASTE, yield is next, etc.
And I love it when taste and productivity are found with the same varieties, as grown by me where I am.
Carolyn