Stephan Kesting makes some really good points in this video. The essential point is that every art has:
1 – Techniques
2 – Equipment
3 – Training Methods
It is the mix of these three that ultimately shape the art. This is why I feel progressive live practise, unlimited by any given rule set (just stafey considerations), is a must (3); and why modern training equipment such as focus mitts and the heavy bag (2) have so much to offer karateka.