My International (derailleurs) is set up with half-steps, and
the bike I'm working up next is going to be set up the same way.(mostly because I already have the components)
Half-steps with a wide rear is the ultimate way to get the widest range, narrow-step gearset with the fewest parts.
Shifting the half-steps on the chainrings is the equivalent of having a one-tooth cog change in the rear.
For people used to shifting 11-sp, it seems ungainly, but the shifting algorithm is really simple.
Either up or down, always shift first on the chainring half-steps (left), then shift in the rear as needed (right).
Generally, you always want to get on the big chainring as soon as you can, so you have that half-step down always waiting for you (exception to this rule would be carrying a big load up a long grade, or cruising at a similar cadence with your friends on 11sp bikes).
The point is you're shifting two levers, left and right, most frequently up front, but it works really well.
The original Lenton GPs were also set up this way, with with 49/46T chainrings.