A lot of techs who are only techs because they were told to get the training, don't keep up with all the new information that comes out all the time...whereas some techs who are really driven by the passion to keep kids safe DO take the time to actually read the LATCH manual, get the yahoo news group updates, and spend time at various messageboards, to keep up...you just never know which type of tech you'll get (hopefully even the ones who don't spend a lot of time keeping up with the information will at least defer to the car and seat manuals, though!)

As for lap and shoulder belts, yes, they are fine to use :)