Suggestion: One way to avoid the issue of straggling ships would be to move your fleet into a clump at the end of your grav well before giving the order to jump. Methinks this would be effective if you like to have your force attack completely en masse, which I agree is the best strategy if logistically possible.
See the problem still happens for me, even if I send my fleet to the edge of a gravity well all together. Its really random, but more often than not they do not coordinate their jump. Sometimes its perfectly flawless, with a slight offset, but others basically turn into kind of like a line of ships jumping. I guess they listened too much in first grade

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