G'Day H2Flow,
The old addage was that when your kite was at 12 o'clock & depowered and you were unable to walk backwards into the wind then you had too much kite. This mainly applied to "c" shaped kites and actually originated back in the days of 2 line kites which had no depower.
This has now changed because of the invention of the flat kite, SLE (Supported Leading Edge or Bridled kite) and also the 5th line setup of kites like the RRD and many others which use the 5th to pull the leading edge down reducing angle of attack.
Now it is possible to walk against the wind in extremely overpowered conditions with relative ease, this however doesn't make it much safer in fact I would suggest it makes situations much more dangerous for beginners should something go wrong.
If you are concerned with how much power to ride with and you are a beginner using a kite with a large depower range ie bow style, try pulling in on the trim to fully depower the kite and then pull the bar to maximum power ie sheet in. If you cannot walk against the wind, then I would say you have too much kite up as a beginner.
As you gain more experience you can certainly hold onto more power and utilise the full range of the kites ability, but without a lot of experience that may come at a heavy price.
You can also check the manufacturers recommended wind range of the particular kite and add say 2 knots wind range for every 10kg above 70 kg of body weight.
Hope this helps. Good winds,
