Chrome,

The question still remains unanswered, why hasn't access to far superior form analysis through high tec. at our fingertips to access and collate a far greater amount of form facts, enabled punters to recognize more than 30% of 'winning horses' ? It should, but it hasn't.
They are not being spotted because they are not being bet into favoritism.

I'd just prices going down is a separate issue and has more to do with a smaller punting market [far greater competition and diversification of the punting dollar especially into new and varied exotics and Sport's betting] and a corresponding increase in bookie overall book percentages and TAB takeout.