As one of the "15ers" myself, I can assure you that your assessment may apply to some, but not to all. I have adopted the 15 approach (more like a 10 approach, actually) because I know that this company has continued its slide downward and, while the worst is behind us, there's a ton of sliding left to do. I predict the complete elimination of what's left of the sales force, which isn't much at this point.
I've watched Merck mercilessly target many good reps for elimination and it sickens me, maybe because I know I could be next. Anyhow, I've cut back on all but the absolutely necessary activity for Merck over the last two years. I've started selling my own commission-only products with the bulk of my time. I've done it out of self-preservation, but I must say I would have NEVER done this to a respectable employer. I'm happy to do it to Merck---Merck has earned this dose of karma, which is EXACTLY what I believe it is. And I'm not alone.
FU Merck.