This suggestion is much more (for me) than a convenience. This is essentially providing a (simple) means to specify a value that changes rarely. Alfhoneses suggestion that rather than making the index follow, but have another value running around that increments whenever primitive restart happens has legs in it and not a bad idea; it just means that one gets the value through another lookup into an array, buffer object or something else. My suggestion with or without Alfhonses modification to it means that the entries in the vertex cache should be discarded at primitive restart. For my use case, that will have no impact on performance because a fixed primitive uses the same value. In general, this idea is just to avoid using up the extra memory and attribute slot needed to get the same functionality. Doing it the way I have to now, the vertex cache is a miss anyways.