For me, the only thing that would make sense is if the OP was referring to the Service Menu of the display. In general, you should be careful when you tweak the Service Menu because it may be possible to damage the unit if you tweak certain parameters.
Generally, however, most calibrators would only tweak the bias and gain in the Service Menu and that should not be a problem. In fact, with the proper instruments and software, it will vastly improve the picture.
Of course, the OP may only be trying to undermine the sales of stores which offer free calibration. That's speculation but I can't help thinking that way cuz the first post is so badly written and with so little information that it's hard to believe that a rep of Panasonic Philippines had actually written it.