Hello99, a very quick glance at the gemara Shabbos 10a, seems to say that each amora would daven in the way he felt comfortable to express what was on his mind. One would dress fancy, one would davka take off his fancy garment so he would not appear chashuv. One would clasp his hands (pachar yadei) another would clasp his hands when it was an eis tzara, as an eved pleading in front of his master, but when it was a time of shalom and prosperity, he would dress fancier (to show his thanks and happiness in the RBSH for his good fortune).
How one takes from this gemara that clasping hands is a bad idea and brings din down on a person is not at all apparent.