An important distinction to make here, is the concept of 'yeild' no longer applies to resource gathering.
The change from 750 to 1000 units per cycle, using titan as an example, does not yield more ore per tile. The amount of ore per tile is fixed, the 250 unit increase simply speeds up the recovery of the ore; this same principal applies to the bot bonus, tuners, and extensive extensions.
If a tile has 385,000 units of ore, that is the maximum amount that tile can yeild. If that was titan, with no bonuses, it would take 385 cycles @ 1000 units per cycle to mine the tile empty.
If your robot has 200% yeild, then you'll mine 3000 units per cycle, and empty the tile in 129 (rounded up) cycles.
With no bonus and 10s cycle times, 385 cycles / 5 modules = 770 s.
With bonus and 10s cycle times, 129 cycles / 5 modules = 258 s.
But, since you really can't get 200% yields without also getting faster cycle times, typically around 5 s at that % range, a Riv MK II can empty a 385,000 unit tile in a little over 2 mins.
(Maxed out, 234% @ 4s would be about a 1.5 min)
Without the reduction in vlume, 385,000 units of titan would have been 19.25U, but as C has said, it's been reduced in half, so it's only 9.63 (ish).
tl;dr - Mining is about time now, not yeild.