Could someone explain this to me? Trying to constrain lights in Solaris

I feel like I understand its meaning but not details? Perhaps a simplified explanation could help.

Might be nice if you could elaborate on where in this description you’re getting stuck. What’s unclear in particular?

In essence it’s saying:

USD is designed to be static / non-dynamic. Hence the nature of a constraint, which is dynamic, is currently not a feature nor a pattern fitting in the current USD ecosystem.

However this does say that, in Houdini’s LOP implementation that acts is that layer above USD it can of course compute a constraint dynamically yet just write the static (or animated) data into USD where it’s not dynamic in nature anymore.

I do agree the wording can be simplified. It uses some terminology that might require some thorough understanding of English and the usage of the word “layer” within a USD context but not meaning an actual USD layer seems like a bad choice.