The "optimised for digital" can mean a couple things. In the case of some lenses (Sony 50/1.4 vs Minolta 50/1.4), they changed the designs slightly so as to prevent inter-reflections between the rear element and the sensor, since a digital sensor is much more reflective than film and would cause a bright spot in the middle of the frame in some situations. So no problems there with film, the lens is just as sharp etc and the new design fixes a problem that film doesn't have.

However, one particular Nikon 70-200/2.8 (I think) was infamous somewhere around 2005 or 2007(?) because a particular revision had the sharpness optimised in the centre (APS-C region) at the expense of sharpness in the rest of the (35mm) frame - this was before Nikon released any full-35mm digital bodies and expected to sell a lot more APS. Made a lot of people pretty angry, too, because the lens performs noticeably worse on any 35mm body (film or digital) compared to the previous revision. I assume with Nikon now selling a lot of high-end 35mm digital that they've released a fixed version since then and (not being a Nikonian) I don't even know which specific revision of the lens was bad. You'll have to ask on the Nikon forums.

So: it depends.