No your expectations are not too high. The sharpmaker is capable of producing really sharp edges and you should be able to achieve that with a pocket knife. What knives are you sharpening?
All good advice above.
If the stones are not hitting the very edge then you aren't sharpening. That is where the sharpie can help, it shows you exactly where you are removing metal.
As EvilD said, it is easy to blame the tool when things aren't working but that is almost never the case. The only time it is the tools fault is when the stones are dirty and even then that is still really the operators fault.
You want to be removing metal from the very edge and you want to use light pressure and you want to be consistent with your angle from stroke to stroke.
Do some searching on here. We have coached many people on sharpening and dont hesitate to ask any more specific questions you may have. We are here to help.
Welcome to the forum!