I don't think it's one or the other. You need to spend some time in the cave to find your bearings and prepare a bit, otherwise you'll be clueless and have skill issues. The mistake is in spending forever doing that - at some point you have exhausted what you can get from the cave, and you need to put it to the test in order to find grounding, and you can do that by going out there and showing what you've been brewing. Finding that balance is a nice thing to pursue in itself, and from what I have seen it seems to be completely different for everyone.