I'm cabin crew and a few years ago my outfit had B737 300/500/400's and every now and again a pilot would hand fly the whole sector and yes you could feel it. The aircraft just rose and sank very gently and felt 'different'. Of course you might say that as we were informed beforehand we would be pre-programed and so our believed sensation could be a placebo. However on two occasions that I can remember I went in to ask them if they were hand flying because it felt like it. And on both occasions they were.