BAL Recommended knotched trowel

[afright]

Just a little query on the old quarter inch notched wall trowel that BAL used to recommend but now they dont,so why were they right years back and now its not recommended the adhesive's are not much different today tiles are fixed more or less the same way,does this mean that they can get it wrong as well ?.

 

[Rookery]

Maybe its due to the size of tiles these days. I very rarely have to use a 6mm notch now.

 

[afright]

But they do not recommend it for even 150x150 tiles the notches were quarter inch every half a inch my query is how can they recommend something then move the goal post.