Is positive reinforcement why things are sounding better?

Just curious if positive reinforcement experiences have occurred for others, and how can you really tell?

Well, just thae fact that you are questioning it makes me think that it is probably not confirmation bias. 

Teles are great so at least that much is truth. Best way to check is to play some songs, then re-insert the previous component and replay. Still good?

When you change something expecting or hoping for an improvement, be honest with yourself. Is it really better? Pros and cons? Do you want to compromise on the cons for the pros so you can stay with the new item? 

I would say it sounds like you have made good choices… because when you don’t you will know it.

Early on I made a few bad choices… although I may not have known it on the first day. One of mine was I found out what grain was in the sound of a used preamplifier.  It took about three days after buying it to hear it… I could not unhear it. I lost a lot on that one… but I immediately had to trade in.

I always try to hedge my bets by always doing enormous amount of research and upgrading no less than 2x the investment. I don’t think I have been disappointed once I made sure I did both.

One thing is that you learn about sound and your tastes and over time will likely make different decisions. Often early choices focus on detail and slam and latter decisions are made on different less easily perceived parameters.