Sterak's Gage Stacking

First off, Sterak's Gage passive +25% base AD can stack, causing spellblade effects to deal much more damage than before. 5 of them stacked increases Skarners triforce damage to 619. Secondly, stacking multiple Sterak's Gages causes your AD under your status to differ from your actual AD, which is only shown if you highlight the stat in your status box. Also, as far as I can tell, having multiple Sterak's Gages can sometimes cause the active effect to not trigger.