Spell Echo bug (in combination with spell cascade?)

I'm currently playing bonestorm + bonecage and I'm running spell cascade + spell echo on my bone cage.

The tooltip doesn't show any increases in DPS when I link Spell Echo, it just shows the decrease in cast speed, but not the damage gained from the echo'ed spell. It does appear to summon more spikes but the area for the echo'd spikes is not increased, while the gem says it should be increased by 30%. Is this a bug?