My '08 that is thrashed on a regular basis, uses maybe a 1/2 quart between oil changes (2 to 3 K) more if I have ridden a lot at a sustained cruising 5K + RPM which BTW is really asking a lot of this bike. I've never had to add oil to keep it between the lines. Not unmanageble if you check the level at gas stops. That is regular maintenance. Now, on the other hand if you need a whole quart every fill up you do have a problem.
I did do the PCV mod and noticed a slight reduction in oil usage, nothing of major consequence. It just made good sense for a single cylinder engine.
Jeez, if it aint between the lines put some oil in it.