Back to confined area techniques - it all comes down to performance and you should not be conducting CA landings, especially 'scary' ones, without adequate performance or you are asking to be included on Davy 07s list.
The ability to hover OGE should be the absolute minimum performance you should consider for GA flying into a CA (or most other flying for that matter) and this would be suitable for 'easy' CAs - the sort where as UK says, you can avoid losing translational lift until you gain the benefit of ground effect.
But, and it is a big but, where obstacles force you into steeper (or eventually vertical) approaches, you really do need more than OGE power and a good working figure is a 10% thrust margin. Work out your max AUM for the OGE hover, then deduct 10% of that figure and make that your new max AUM for your CA - adjust fuel/pax/luggage weights accordingly.
The 10% still isn't a huge amount of extra power but it should allow you some margin for error when the wind isn't as expected or you don't fly the approach quite as well as you might or you suddenly lose the effect of the wind as you descend behind trees.
If you can't meet the required performance criteria then don't go into the CA just because you have a lunch/dinner/hot date - the R22 isn't forgiving in limited power scenarios (because it doesn't have much to start with) and it is all too easy to overpitch, droop the Nr, start to lose TR effectiveness and generally end up in a world of hurt.
I'm sure that most pilots have been taught that if you can see the far end of the landing area in a CA then you can make a single angle approach and if you can't you should make an approach to the obstacles on the near side of the CA until you can see the far end. If you can't see the far end of the CA at all on the approach then you are into a hover OGE and vertical descent (with suitable lateral and forward markers).
A single angle approach invites the 'keep TL until the ground effect kicks in' technique and may sucker you into attempting this with only OGE (or even less) power available - the point where you can get severely embarrassed is when there are obstacles upwind which mask the wind effect you are enjoying at height and suddenly drop you off TL with few options but a heavy or overpitched landing.
Lastly, don't forget that having got in there, you have to be able to get out and an easy approach may lead to a more difficult departure - again the 10% thrust margin is what you need for vertical departures.
Treat CAs with respect folks and keep some performance in hand.