Just one more thing. Is there such a thing as cross compatibility between say Shimano and Sram etc etc.as far as shifters and derailleurs go?

In my instance, what i am asking is if the SL-R460 shifters would have any chance of working together with my Sram Apex 2x10 RD (&FD) or is the cable pull too sensitive/specific for each brand that such a thing would be out of the question?

Could someone also (please) elaborate on the pull ratio chart and what this means:

CAPACITY,
MAX FRONT DIFFERENTIAL,
MIN LOW,

Been looking at the max low to see how many each derailleur can tackle, but the rest is a little greek excuse my french.