The problem is that people need to try products on different types of substrates with different degrees of contamination! Sadly lots of people are sceptical and often frightened to try other methods! Just because hypo works on some things as do acids does not mean we have to use themall the time especially when, gentler more enviromentally friendly cleaning methods work just as well albeit, a little slower, so what? By all means knock people and advice if you have tried the methods yourself but don't just knock something because you think it's wrong. Chris Scott and I have had a few run ins over the last few years but in the main he is a very skilled professional with a great understanding of the task at hand and most of the time he employs the best and most efficient methods to tackle specific problems.