Agree with TD. Not trying to be nice either, but sometimes a bit of humble pie is needed. Even though it`s quite obvious that the deciscion to begin the takeoff run solely lies with the 2 pilots. But what is interesting is the reason for the mistake. What lies behind etc.
Most of us, myself included, keep a more open eye and ear when clouds and visibility deteriorate. We all know that taxiway markings are blue. But as TD said, this has happened before. Low vis accidents, runway incursions, wrong or dubious procedures will continue to happen and we cannot 100% safeguard against them. Loss of situational awareness is another problem, and can just as easily happen in good conditions as bad. Tenerife comes to mind.. And the landing on taxiway Y in Bodø (which parallels the runway). We can all make mistakes.