Last year an article in the cycling press asked the question "are power meters killing the art of coaching?" It's conclusion, after some detectable anti-power sentiment, was that coach-rider communication is key and therefore the art of coaching must trump the use of power data, positioned we suppose as the scientific opposition.
Of course the infamous Dr Ferrari to this day includes the caption "coaching is art" on his website 53x12.com and he has a point. Science gives us models of the world, but the best users of those models know how to combine and interpret quite a few, having regard for their limitations and applicability to unique circumstances such as events and riders. This process, intuition, triangulation, call it what you will, is well described as an art form and fits with the role of a coach.
But to suggest that power meters or power data might be somehow diminishing, rather than enhancing or enabling this art, is frankly the wrong question. What makes a coach-rider relationship flourish, as the article points out, is communication. Communication requires language, and we believe that the most powerful language the sport now has is power itself.
Now why is power the key to coach-rider communication?
The language of power based training allows us to be succinct and expressive about the makeup of training sessions, with great accuracy. Imagine, for example, being an engineer before anybody had developed a vocabulary to describe different building designs. You'd be using dozens of words to describe concepts that now need one or two. Training sessions are the same - once a rider understands what is a "2x20 @ 105% FTP" communication is eased and enhanced.
A doctor would have a hard time evaluating a critically ill patient without access to a modern suite of diagnostic capabilities such as blood and ECG data. These tools reveal more about the patient's state than words will ever do and anyone who has ever laid in a hospital bed will recognise that at doctors rounds far more time is invested in checking these diagnostics than asking the patient how he is. In cycling the diagnostic capability of power - pre or post training and pre or post race - simply trumps a lot of verbal communication in it's richness and value. The really important communication then becomes the eventual diagnosis, prognosis or prescription facilitated by the data.
How hard & how fast
Your assessment of RPE is not my assessment, just as your heart rate is not my heart rate. Some people are simply terrible at evaluating how close they are/were to blowing, especially relatively new bike riders. Cycling was crying out for an objective measure of intensity before power came along but coaches and riders must communicate on three major topics: duration, intensity and frequency of training. Only power allows riders to be benchmarked on ability. Power = Speed, with just a few parameters in the middle. Rider benchmarking and goal setting, fundamental parts of the coaching process, are practically impossible without power data. You cannot communicate what you cannot define.
How sick or how injured
Sickness often manifests itself as the inability to achieve a certain intensity while injuries tend to be evident at certain power outputs, torques or cadences. Power data is therefore incredibly expressive when the unfortunate time comes to communicate either of these problems.
Form and history
A rider without a history of power data has no context in which a coach can place him. What is his baseline, untrained level of fitness? How far is he above that, and how much headroom does he have? What types of training has he best responded to? Some coaches would admit that coaching riders without power data feels almost dishonest. Dishonest because it imposes some very real limits to the amount of value a coach can add.
We live in an internet age where a significant number of riders have never met their coach, nor will they ever really need to. Cycling is not football or any other team sport characterised by group, face-to-face training sessions that may or may not end in the pub. Power data is not a web protocol but it might as well be. It opens all kinds of possibilities in terms of two way, coach-rider-coach communication, which nowadays increasingly has to be virtual.
Power is changing the game. Don't be one of the naysayers who claim it's damaging racing or coaching or it might just damage your job.