I would like to preface this with the statement that I am relatively new to DE. I have been using a badger brush/soap for about a year and a merkur HD for just over a month. I have tried a merkur (yikes...won't be doing that again), 3 feathers, a red pack israeli, a derby, and a crystal. I have to agree completely that the feather is the sharpest. I have had 3 nicks, all from the feathers. However.....
In my opinion, it was using feathers that has taught me correct shave technique. They are instant feedback....you use too much (or any) pressure, nick. You use the wrong blade angle...nick. the last 15 shaves with feathers have been extremely close, extremely comfortable, irritation free, nick free. Thought I should add that I started with the merkur, followed by the israeli, derby, and crystal, and using those blades allowed me to use too much pressure! They almost reinforced incorrect shaving technique that will not work with sharper blades or a fresh blade! IMO, we should be telling people who are learning to start with feathers, warn them they are sharp, and that when the get a nick, they are doing something incorrectly!
Just my 0.02
In my opinion, it was using feathers that has taught me correct shave technique. They are instant feedback....you use too much (or any) pressure, nick. You use the wrong blade angle...nick. the last 15 shaves with feathers have been extremely close, extremely comfortable, irritation free, nick free. Thought I should add that I started with the merkur, followed by the israeli, derby, and crystal, and using those blades allowed me to use too much pressure! They almost reinforced incorrect shaving technique that will not work with sharper blades or a fresh blade! IMO, we should be telling people who are learning to start with feathers, warn them they are sharp, and that when the get a nick, they are doing something incorrectly!
Just my 0.02