Yikes, make a generic statement and have it pulled apart by everyone with the exceptions! I thought it was only old Sachs stuff that was compatible with Shimano, rather than the SRAM ESP stuff? I might be mis-remembering that though. SRAM did do Rocket (X7 equiv) and Attack (X9 equiv) RH 9spd trigger shifters which were specifically designed to be Shimano compatible, but none of their proper X-range stuff was. Aside from that 'blip' none of their proprietary 9/10/11spd ranges have been compatible with each other in the last twenty years, at least. You could just about make 10spd (perhaps it was 11spd) work with the addition of a spacer under the cable on the mech clamp, but that was definitely dubious in its effectiveness. Front mechs all worked across the two as IIRC they were always 1:1 (hence no LH Rocket/Attack), but again, I might be wrong on the ratio.