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It hits as frequently with 1.5 as anything.

A battlefield workaround that works sometimes is repeatedly (double-clicking madly) ordering your soldiers to run elsewhere and once they're out of the buggy loop order them to walk up the tower again. If ordering towards a certain location doesn't work, try another.

It doesn't work many of the times and the bug hits almost any time besieging a large stone walled city. That's why I use sap points assaulting them and build siege towers only to exploit their magic laser gun capability in case the enemy sallies.
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