SE has acknowledged the delay for DRG which is why they implemented Spirit and Soul Jump(they increased the TP for these abilities from 1.5->2 and from 2->3 I believe for Spirit and Soul respectively.) Their logic was that the TP generated by Jump and High Jump did not warrant their use since they slowed down the Dragoon's attack speed. Because of this, Jumps were actually not worth interrupting your attack rounds since they gave as much TP as a regular hit but had a 2 second delay which otherwise wouldn't have been there at all if you didn't Jump. Spirit and Soul Jump were implemented to give you 2-3 attack rounds worth of TP to justify the delay.