a couple of things here.
1. no girl works 4 months straight without having to take a few days/weeks off. Look at bree olson, sasha grey, etc. etc. The more popular you are, the more you work, the more you open yourself up to bodily problems.
2. even girls that work 4-5 times a week, you are forgetting that they are doing BJs and HJs or solo stuff as well, which pays less.
3. i heard that the mainstream agency fee is significantly higher than the cut taken my porn agents.
4. there is no hole on your resume doing mainstream. porn? a different story