What I found, when I was using the DPA4061s > Oade Mod SBM1 > DAT, was that without the rolloff on, the nearby clapping, especially right next to you, would overload the waveform and make a huge SNAP sound that would be unrepairable, especially during the music.
I have some Bill Frisell tapes that are almost ruined by leaving that filter off. When switched on, it would minimize slightly the impact and make it something I could lessen in post. I'll dig up some old tapes and post a picture...
That's most likey simply an issue of the clapping being significantly louder than the music and the levels set so the recording clips during applause. Switching in the filter lowers the SPL level of the clap by cutting some of it's bass energy, yet the same result (without the low cut effecting the frequency response of the music) could be obtained by recording at a lower level. Of course, in doing that the recorded level of the music would also be lower. The crucial question is then: "does that make a difference?"
The answer for me has been, "no, it doesn't". The noise floor of the room has always been higher than that of my equipment, even if I set levels to accommodate a close, loud clapper. So for quiet material I simply set levels by clapping loudly myself before hand.
[realworld example: Bill Frisell, 4060>MMA6000 or CA-UGLY>R-09 (24bit) <<which is probably only recording 16 or 17 useful bits anyway, but that's a different discussion]