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I disagree.
What and who defines excessive?
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And I agree with your disagreeing.
It's very vague to talk about the possibility of venial sin when "excessive pleasure" is sought after/experienced in sex.
Let's apply the same thinking to food. There's no way I'm
not going to experience pleasure eating a simple, common food like a hamburger when I'm starving hungry. But all we must do as Catholics is 1) first bless our food, thanking Him for His great bounty, and 2) stay within the bounds of temperance (don't eat too fast, or too much, or be too picky, etc.) So as long as you avoid those excesses, as to the rest, the inevitable pleasure of eating was put there by God and it's not evil! Consider it a small consolation from God, to remind us something of His goodness.
We're not Puritans or Manicheans. Dualism is a heresy: the body wasn't created by the "evil god". No, our body AND our soul were both created good by God, Who is all-perfect.
So if you are staying within God's bounds (for married relations, that would just involve being married and being open to life -- ending all activities in the proper way), then there is no need to get SCRUPLES about it.