[bcrdukes]

Thanks for that!

My only suspicion or theory to this scalding espresso problem are poorly maintained machines.

If a shop has three group heads, I would expect (or at least hope!) they are cycling through the various group heads, or at least maximizing their group heads for productivity. However, the general observation is that is that most baristas will only stick to one group head throughout their shift, leaving the other two group heads sitting idle. I would attribute to the grouphead flush a problem of the past when the E61 group head was abundant, but with companies like LM et al, these issues have been solved for the most part.