Thanks for your answers folks.
I'm au fait with the rear shifting combos, but not with any mix-matching using shimano's front indexing, although I seem to recall their road and MTB indexing is different
True for early levers (all pointy top ones and first generation round top). After that they went to a big-jump index system (a la Shimano) for Xenon to Centaur.Campagnolo doesn't use indexing for the front, but rather a ratcheting system. So the left Ergo levers work with pretty much any front changer. Which is why I like them, besides the good looks of the early Ergo levers of course.
I'm with you on the friction shifting on the front is the way to go hamster. My gevenalle inspired set up works so great I even switched the back to friction. No more faffing about.If you look at Spa Cycles, who carry about the best range, you will see two sets of rings, listed as middle and inner for the 130pcd size. One set are ramped, the others are not.
https://spacycles.co.uk/m8b0s113p0/Drivetrain/Chainrings-TA
Also it's only really an issue with indexed front shifting (thrrrrrp-thrrrrrp-thrrrrrp).
Personally I cannot bear indexed front shifting (apart from Campag micro-adjust) as it seems always to rub and created as many problems as it solved.