Didn't make it on the way out. Left MAN on LH949, Saturday 22 Aug. Arrived at bus gate B65 or something, quick passport check, turned right and walked what must be the long way round to A48, no tunnel. But was still at security 50 mins before take off. However, security speed was was glacial. Only about 30 people, took me 35 mins to get through. The fast track queue just fed into one main queue, anyway. One security queue had a whole body scanner which was playing up, the other had elderly and wheelchair passengers going straight to the front. Security staff were totally disinterested, like they were on a semi-strike.

Worse was to come, when I had to go to the Lufthansa service center to get re-booked on the next flight. I had to queue for 30 mins to just get in the place, it was all very chaotic, not enough staff processing customers. LH staff seemed to think it was my fault I didn't make the connection. "The incoming flight was on time". Eventually, after waiting for 2hrs, they put me on the 12:30 to NUE.
But we were then sat on the tarmac for 60 mins while they changed a tyre on the plane. And I was sat next to a morbidly obese passenger. FRA-NUE was only a 25 min hop, thank God.
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On the return leg, no problems. Through NUE security in about 60 secs. Left 5 mins early from NUE. Bussed to an A gate at FRA, LH rep told me to go to A15, then lift down, then through "the tunnel" to B. Quick passport check before going to B28. Only 15 mins transfer time, if that.
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On a positive note, I now know how to find "the tunnel". This seems a quicker way of getting between A and B.
On the minus side, FRA uses lots of bus transfers from tarmac to gate. These can really eat into your allowed transfer time.