The order of enhancements in the slots makes no difference.
The 3 slot thing, which you're misunderstanding, is that when you're using SO's (Single origin enhancements, or something with equal level buff, like YO's or HO's), you only get a good buff from 3 or less enhancements of the same type, more is pretty much a waste. (So 3 damage is good, but you shouldn't add 4th damage after that. Accuracies can be added after 3 damage just fine however, as can any other type).
i cant belive i've been playing for as long as i have and did not kno that 
TYVM for letting me kno that
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i have been working on my only deffender L8ly which is a emp/rad.
I read up on the emp/ and kno what i should be slotting, but am unsure about what to slot 4 the /rad part
i read 2 diffrent ways and wondered which would be best to go with my emp powers
dmg/dmg/dmg/acc/acc/. . . . and acc/acc/dmg/dmg/dmg/. . .
i just want to make the most out ov the bonus frm the 1st 3 slots for my toon
could anyone help or give advise(even better with an expanation) ?
all help and/or veiws will be much appreceated
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