The world we live in is far from perfect, errors of judgement will be made and its important to modify the way things are done as a result, thats called continuous improvement or progress. BUT, its important not to forget that ultimately the buck stops with the PIC, it is ultimately the captains responsibility, end of. There seems to be an undercurrent of "blame the circumstances not the crew", i'm sorry it doesnt work like that. Aviation safety is so high because of the fear of what will happen to the individual if he/she does something wrong. Its a superb motivator to maintain standards. Yes, there are circumstances and events beyond the crews control but has already been stated on here, there is NO excuse for a taxiing prang.