Still remember the first day out of supervision, proud to have 150 hours 737 under my belt. Flew with an old geezer a sector to barcelona, he was flying, manually of course the whole time without any automation on. In the descent i noticed the aircraft leaving the intendet track, called it out two times, looked over to find my handflying old captain thoroughly asleep
Of course i let him sleep and just flew the damn thing myself until he woke up 20 minutes later.
12 hours later after our duty we had a couple beers and talked it over, end result was i never learned as much as from that chap, especially in regards to flying without all that automatic stuff.
Nowadays i enjoy all the different ways of doing the right thing, the small techniques and all i can learn from it, be it a good or a bad example. The only times im really scared is when i have to fly as a safety on the jump seat with new hires. And every time i have to ask myself: was i really that bad myself back then?