sorry, but your problem is that your opponent is smarter and didnot choosed doctrine in the first minutes like lots of noobs does.
It should be common, like in coh1 that you only choose doctrine when you know your enemys, so he saw he needs a Jagd against you, and you got rekt. Nothing wrong with it.
It's a fair comment, but a lot more applicable to Axis players rather than the Soviets who often rely on elite infantry from these doctrines.
I played hundreds of hours in VCoH and it was a more common thing to do then, but let's be honest most of the time you'd pick Infantry as American and Commandos as Brits; Terror as Wehr and ? as PE, almost certain in 1v1 if you look at the tournament replays, it was not common to deviate from that.
Same in CoH2 with Shock Rifle being common for IS-2, along with a few other common commanders. How often do you see Partisans for example?
What doctrine would you suggest I plan to when I see a JagdT? Forgoing elite troops until I see Panzer Fusiliers, which were not present this game. Should I be stocking my fuel in preparation for a heavy tank or spending it freely with no doctrine picked as I don't know which commander he has gone. Your advice is completely useless in countering JagdT; if you watch most casted games they pick their doctrines very early on. The Germans have more flexibility in this generally.