Most plywoods use RF, UF or MF glues which are hard enough to seriously abrade tool steel cutters and will even cause wear on HSS cutters (carbides are OK, though). For small quantities you'll get away with it, but if you need to do a lot budget for a trip to the sharpeners. You may also find the cross grain layers spelching out. Plywood will, however plane well with a low angle (block) plane.
I do this occasionally with MDF and plywood - I don't make a habit of it. Someone suggested I reserve the furthest point of knives - ie with the fence pushed all the way back - for this task (and only take off very small amounts). Was a good idea - I'm not usually using all 10" of the bed anyway. You then just nudge the fence along an inch or so for other jointing operations. Sometimes you just need a straight edge on man made board. I did check out carbide planer knives but at £150 I gave it a miss(!)
I do now often try and use a hand plane for getting a straight edge - good practice for me. But not usually that successful!