I have zoned from Qeynos South to Erud's Crossing by swimming. you can zone
while swimming. i swam all the way from Qeynos to Erud's isle. and i teleported
many times underwater without problem. i think the gate collapse only happens
when someone is STANDING on your gate position. because the gate collapse
happen to me only 4 times and those 4 times happen ALL together within a period
of 1 min. where all my gate just either fail or collapse. but after i waited
awhile, it worked fine.