You guys can go find the Steve Neal tempo training topics if you are interested. You can find others:
I did a tempo build (built out to 4x20 minutes over a 2-3 months starting in January) and achieved my best results in recent years by June.
I really think there is something to a high volume of sub threshold intervals. One could find numerous other examples. The famous “double threshold” is not really threshold. It’s a lactate controlled set of intervals that ends up being more tempo / sweet spot to use cycling lingo. Marius Bakken would be another source to look up.
I think what tempo training does is give one a high training load - CTL in cycling analytics. You could get there any number of ways (high volume z2, threshold intervals). Tempo intervals though seem to be easier to recover from.