Although @freestar8n results are interesting and as is pointed out, this information only suggests improvement under the skies with plate solve. The mount coordinates only roughly tell us what plate solve will produce,
This thread has wondered around considerably. It really does not matter how accurate a particular mount does a slew. What we want to know is if you do a delta slew can you get as good a result as doing a sync and slew.
So may I suggest limiting further posts to this thread to results comparing the released SGP with the test version that Jared provided. If it is as good, then the sync can be removed which will help those with sky models and not hurt those without models. We need under sky results from many mounts to validate this proposed change.