Stressing how serious it is about putting computers onto laps, Data General Corp yesterday added a new model to its Data General/One line: the 2T weighs under 12 lbs, and claims an an exclusive combination of features including a backlit, supertwist LCD screen, dual-speed CPU 80% faster than previous model,a 10Mb 3.5 Winchester and internal removable batteries; it runs at a user-selectable 7.14MHz or 4.77MHz against 4.0MHz for the previous model and the entry price of $1,695 includes the new display, 512Kb CPU and one 3.5 floppy; with light-emitting, electroluminescent screen the same configuration is $2,695, and the 2T takes up to 2.5Mb memory, while the electro-luminenscent version runs over two hours on an external battery pack.