Definitely good points. So, this poses to us the question if fluoride-free toothpastes are a feasible strategy to combat EC, and if it is safe to recommend as a treatment option.
Personally, I agree with 145078 that fluoride is critical in maintaining optimal health of teeth, and reducing the risk of bacterial infections. If we avoid fluoride, chances are we will get uncontrolled bacterial or even fungal growth, which is likely to at least affect the vermillion border of the lips, probably setting the healing of EC even further back.
From my personal experience and believes I would state that Monsterlips' treatment of simply keeping good oral health (brushing teeth daily, but no antibacterial mouthwater) and daily cleaning of the lip skin with fluoride-containing, SLS-free toothpaste and SLS-free natural-based soap respectively, makes more sense and yields more hopeful results.
After about 1 month of trying the above mentioned good oral health strategy, I noticed that the peeling of my top lip reduced alot (to only the middle portion and about 0.5 cm on either sides), in contrast to almost the entire vermillion border of my upper lip!!). Also, my bottom lip seems to peel slightly slower, and in particular peeling of less thick scabs (I would estimate about 30 - 50% less thick). I haven not yet noticed a reduction in the peeling area of my bottom lip, but then again, I'm only about 1 month underway... Perhaps a downside is that they seem to dry out a bit faster, so I probably should drink more water or so.
Still, if using fluoride-free paste does indeed tend to "cure" someone, then I can understand you would go for that. I would check with a dentist in this case though..