I don't think that's necessarily true. Why would water and a cleaning solution be a "recipe for disaster" with glass carboys? The only problem (and it's a big one) would be wide fluctuations in temperature, such as filling a cold carboy with hot water. The presence/absence of PBW or Oxyclean is immaterial - it's the hot water that's stressing the cold glass, creating weak spots and priming it to eventually fracture under otherwise tolerable loads.
Because cleaning solutions make things slippery. At least what I use which is PBW. Maybe you have super tacky skin on your hand but I don't.