Nope, he means 70 mph (113 km/h), and yes, you just gotta pull out of a T junction and go; no merging lane, no on-ramp. That's a dual carriageway, characterised by two lanes and a central barrier (single carriageways are usually national speed limit, i.e. 60 mph). Bear in mind that as with everywhere else, most people are travelling 10 - 20 mph over the indicated speed limit (and thus probably travelling around 75-80 real mph). Underpowered automatics are death traps. That said I drive a BMW 330D (straight 6 3L diesel) manual, which probably would be fine as an automatic.

The idea of offloading software functions onto custom hardware built around a TTA is interesting - 5 years ago I used to work for Critical Blue who were writing software to design and build those custom processors and optimise an ISA for them. Worth a look.