Not if you do the skip bleach to the print, not the negative.
But if you skip bleach the negative, you gain a lot of density as if you had overexposed the negative by one stop, maybe one and a half stop. So you may want to rate the stock a stop slower to compensate.
But if you do it the print, then what happens is that you lose a lot of shadow detail, so you may want to add more fill to compensate.
Flashing lifts the blacks but it doesn't affect the highlights, so you don't need to compensate, exposure-wise. But it helps to expose consistently because if you have a 10% flash, for example, but one shot is a half-stop darker than it should be, then that same 10% flash looks heavier on that underexposed subject compared to how it looks on the correctly exposed subject.
If you can't flash, you could consider using a heavier UltraCon filter instead.
I also smoked sets when doing a movie with neg flashing and a silver retention process for the prints (and used less flashing in those scenes)