I find Correspondence Chess quite stressful. While in a normal OTB game you might spend 4 hours worrying about the game, in CC you are more than likely to spend 4 months. And not just one game, but 6 or 10 or 12 at a time. It is almost like you have been given permanent chess "homework", and there are no school holidays.
Of course that doesn't mean you shouldn't play CC. One of the reasons for playing CC is that is it like homework, and if you do it right you learn new ideas. Towards the end of last year I began two friendly matches as part of the an Australian team (against Finland) and a combined Australian/New Zealand team (against Portugal). (Eagle eyed readers may wonder why I'm not playing under the Papua New Guinea flag, as I do in OTB chess. This is because PNG is not part of the ICCF) Even those these are titled "Friendly" matches, they are still team matches, and it is still country v country.
For the Finland match I guess the team captain took pity on me (as it was my first CC international) and put me on a lower board. Even then it was still hard work as my opponent employed a defensive, but solid strategy in both games. In fact the games make an interesting pair as I employed similar ideas in both games, despite starting with different colours for each.
Here is the game I had as white. I've abridged the notes down from the 4 pages of variations I looked at during the game.
Press,S - Karpoff,K [B01]
1.e4 d5 2.exd5 Qxd5 3.Nc3 Qd8 4.d4 Nf6 5.Nf3 e6 6.Bd3 Be7 7.0-0 0-0 8.Be3 Nbd7 9.Qe2 Re8 [ 9...c5] 10.a3 c6 11.Rad1 Nf8?! Allowing my knight to take up residence on e5. 12.Ne5 Ng6 After my other knight comes to e4, Black cannot take on e5 for tactical reasons. 13.Ne4 Rf8 [ 13...Nxe5? 14.Nxf6+ gxf6 ( 14...Bxf6?? 15.dxe5) 15.dxe5+-] 14.Ng5 I've always thought that in any game where I could play Neg5, I'd be close to winning. 14...Qc7 15.f4 Nd5(D)
It would be unkind to call this a blunder, although it meets with a tactical refutation. I spent a substantial amount of time (3 or 4 hours at least) making sure the next move worked. 16.Nxh7! Nxe3 [ 16...Kxh7 17.Qh5+ Kg8 18.Nxf7! was one of the lines I needed to find to make the idea work. 18...Rxf7 19.Bxg6 Nf6 20.Bxf7+ Kf8 21.Qg6+-] 17.Qxe3! In OTB I would have reflexively taken on f8, which is OK, but not the most exact move. 17...Nxe5 The knight on h7 is still taboo. 18.fxe5 Rd8 19.Qf3 And even here I spent a great degree of time deciding between the move I played and Qh3. As it turns out, both are good. 1-0