tarash defence

The usual move is 8. Nf6 and if 9. Qd2 h6 with the idea of unpinning the knight as soon as possible. See Aagaard's "Meeting 1. d4", the chapter on the Hennig-Schara Gambit.

This is the Schara Gambit, not a main line Tarrasch.
I believe here 8. Bg5 isn't a very good move. Black just plays Nf6 and equalises. The better move for white is just 8. Nf3.
I much prefer the main line Tarrasch. It's a dynamic, aggressive opening and more sound than the gambit line.
Black is encouraging an IQP position in which they have open files and diagonals for an attack. The Panov Attack of the Caro-Kann is essentially the colours reversed version of this.
The Tarrasch "taxonomy" more or less is about
Scharra-von Hennig
The Swedish variation
The Dubov
The "classical" line in the Rubinstein
Also important to know is the Marshall gambit
The main dxc line
and a side-kick, the Tarrasch Gambit
In all the above, White has played 3. Nc3. The Tarrasch is playable with 3. Nf3 though it's common for Black to resort to some other flavor of QGD in that case.
In a post above there are parallels drawn with the Panov. This only happens only with the 5. ..g6 lines in the Panov ( not even the 6. ..g6 lines ).
Both players need to know a fair share of theory in the Tarrasch, as it usually leads to sharp positions, Spassky played the Tarrasch, the young Kasparov and other greats in the past.
The Tarrasch is a sound opening, a good choice vs 3. Nc3 and in my experience when played between two equal players who know it well, it tends to lead to a "fighting draw".
I disagree....the iqp is more of a disadvantage than being an advantage.... it's not an immediate win like the englund,but still it's not an ideal choice for a club player
The IQP is fine, it's a core pawn structure in chess, discussed in every single pawn structure book, and one needs to know how to play with it and against it.
The Tarrasch is also fine and sound.
"He who fears an isolated Queen's Pawn should give up Chess", Tarrasch
It's okay but the thing is that to a 1300 it's more like a weakness.They probably won't be able to utilise it and that will remain a weakness in the endgame
There's little way around the IQP, it's almost everywhere, in the Caro, QGA, Nimzo, c3 Sicilian, Italian, French. Eventually it's a structure that will appear, one way or another, so everyone, including 1300s, will learn it either by studying it or by playing it.