Actually, modern twins like the 757,767 and 777 have so much reserve power that losing an engine on takeoff generally doesn't pose much of a problem to an alert crew. Last November a Malaysia Airlines 777 with 300 people on board lost several engine parts during takeoff from Stockholm, forcing it to return. The plane, which was headed to Kuala Lumpur, turned around after dumping fuel and landed safely at Stockholm's Arlanda airport.
Admittedly, scraping the tail at the same time would be alarming, but shouldn't prevent a takeoff unless the crew went mad and held the control columns back so far that they lost lift and flying speed. Tail scraping, other than deliberately during certification trials, is exceptionally rare, and tends to jeopardise a pilot's career.
The Handley-Page
Victor that I crewed in my RAF days occasionally did it because of the curious planform of the wings (crescent) and frequent exercizes to achieve a "Four Minute Takeoff," during the high-alert times like the Cuban Missile Crisis, which involved sprinting to the aircraft, starting engines and performing a "rolling takeoff" - actually speeding up on the taxiway and beginning the takeoff roll before entering the runway itself - in order to be airborne in 240 seconds from the alarm going off (instead of the usual 25 minutes). The Victor had a small wheel similar to a nose gear wheel under the tail which acted to protect the fuselage in the event the pilot was a little too enthusiastic in rotating.
We performed this miracle for the US Gen. Norstadt who was visiting the base one time as part of a tour in his capacity as NATO Commander-in-Chief. Unfortunately, it was raining and the plane in front of us hot-dogged the turn onto the runway just a little too fast, skidding off into the mud and jamming it for the rest of us. Norstadt was not too impressed.
A funny thing about his visit. We'd been expecting him to arrive in the very latest of US jet, like a USAF B707. What he actually came in was a venerable piston-engined Lockheed Constellation.