I also heard that the break out boards which were in your link need to be soldered to the PSU otherwise they blow or burn due to resistance if there is loose connection.
You have worked on tens and thousands of miners? Man you must be a pro then. Any other best practices? Do you run your machines on 208 or 240?
It really depends on how old the breakout board is. I know for a fact those parallel miner breakout boards are so stiff you really have to jam them on the PSU. As long as you arent disconnecting and reconnecting them so much the pins stretch, you should never have a problem with loose connections. If you buy an old, beat up PSU with an old breakout board that could be a concern.
I have been mining professionally for 3 years, which in this industry is a long time. If you look at PSU ratings 240 is the max recommended input voltage on most all of them so I wouldnt try and push them that high. All of mine are 208 with the transformer turned up a little bit to get as close to 220 at the PDU plugs as possible.