when I recently flew to new orleans the guy at the ticket counter told me basically the same thing. I had 1 gigantic bag that I had packed everything into and upon returning home it was overweight, I had to redistribute some things between bags so I wouldnt have to pay extra fees, he pointedly told me that I should carry my laptop, playstation 2 and cd player onto the plane with me as things like that have a tendency to dispear, he said this not as a corporate airplane guy giving me a generic warning but in more of a whisper from someone who had seen it happen.

Pretty crazy

i always carry my valuables in my carry-on. then, if they want my shampoo or clothes from my big suitcase, they're welcome to them. i would suggest in cases where special equipment is needed, for example, scuba equipment, skiing, tripods, etc. to just ups it to your destination a few days before you leave. most hotels will receive packages for you in advance of your visit.