Not quite I'm sorry, I'm trying very hard honestly. The more you can put in the more you will get out and vice versa? So a set of R501s are not capable of returning what (extreme example I know) Froome could put in, but I would be unlikely to put in sufficient to see the benefits which his kit offers?
May I ask what you think it was which enabled you to make such a difference when you changed your wheels, I assume the PCC 10 is a 10mile TT?
Yip the PCC10 is a 10mile time trial.
So there is a benefit to be had in average speed but only if you are good enough to achieve it and you will only see anything more than a marginal gain if you are starting with equipment which is well below the level which your ability will get the best out of?
Yip, thats a good way to put it. Also like mugshot says the improvement from a old £130 wheelset to a £300 wheelset is massive IME if you can achieve speeds to get the most out of it (you are at the threshold of speed where marginal gains are important) but a the difference between a £300 wheelset and a £1k wheelset isn't notable at my level.
FWIW, I borrowed a £1k front wheel last week and I can't quantify it but I don't think it performed much better than my £70 Khasim, it maybe did slightly but its certainly a decreasing return.
Beyond the performance factor though there also the 'bling' facto though