The magic words are SLR / SuperSLR / New Super SLR.
Shimano brakes traditionally used a cable pull called SLR or Super SLR.
Some years back, they revised their levers and calipers to a new standard, called New Super SLR (catchy, huh?)
This pulls about 20% more cable travel, but at a corresponding reduction in cable tension.
All shimano road kit is NS-SLR and has been for some time. I can't talk to non-road kit.
Certainly with normal road rim brakes, you don't want to mix between the two. Eg new NS-SLR levers are VERY wooden with older SLR calipers. You need the grip strength of a gorilla to generate the higher cable tensions the old caliper needs from the new levers.
How campag and 3rd party mfrs fit into this picture, I just don't know.
Many 3rd party calipers I've seen simply don't specify if they are for trad SLR or NS-SLR.
It's almost a secret.
The simplistic guide to Shimano STI levers (combined gear and brake levers for drop bars)...
Old style side exit gear cables have short pull cable on the brake and were designed to work with dual pivot brakes at the time, these road callipers were quite limited on tyre size and mudguard options and the levers really didn't work with V brakes, for larger tyre options like on tourers canti's were the system fitted to accommodate fatter tyre set ups.
Newer under the bar tape gear cable style pull more brake cable and work well with their matching dual pivot brakes, which are designed to go together, the later road callipers do acommodate a bit more tyre/mudguard choice and the levers can work with V brakes, but a long barrel adjuster is really usefull for the V's.
The older Shimano levers pulled about the same amount of brake cable as Campag, who we think haven't done any major changes to their brake cable pull.
TRP claim the Spyres are compatible with all drop bar brake levers and were around before the Shimano change over so will be Campag lever compatible.
TRP HyRd claim compatibility with Shimano/SRAM 11 speed levers so are unlikely to work well with Campag.
Are there any (safe) cable routing tricks that would make HyRd work with lower pull levers? - I haven't seen anything. With any hydraulic system the actuator lever/master cylinder must return to it's fully relaxed position to let the fluid levels sort themselves out and self adjust for pad wear etc.
All disc brake systems work a lot better if the disc is true.