When 4.0 came out, Dragoon required 4 eyes to enter Life of the Dragon (LotD). The way Dragoon was developed for Stormblood was such that Blood for Blood would always be available during a Dragoon's LotD phase to allow for 2x Nastronds to be buffed for each B4B. This was because it generally took about 90 seconds between each LoTD and Blood for Blood is an 80 sec recast, giving some wiggle room for handling mechanics or lag, etc.

Since the update which changed DRG such that it only needs 3 eyes to enter LoTD, this threw the synergy of B4B out of whack. Yes, it's true that DRG can still alter their rotation to get 2 Nastronds under every B4B, but the rotation is awkward and non-intuitive because you have to delay your first LotD window by blowing your first and second Geirskogul and holding a 4th Dive Ready until your 3th Geirskogul comes up. This I think ruined the elegance of Dragoon's rotation and made it needlessly clunky, not complex or dynamic. I think anyone who plays DRG to a high level understands how awkward it is to hold/delay GK and sit on a 4th eye (sometimes cutting it close with B4B window and potentially losing the 4th eye). Would be nice if they shortened B4B recast (as the cost of some potency), since the whole theme of the SB revamps to each job was to simplify the rotations and make them less clunky.