User blog comment:AYET/Luffy alone or combined effort/@comment-7614831-20150517173312/@comment-7614831-20150519083349

I'd agree that Marineford is a better basis from which to judge the varying capabilities of the shichibukai than geographical location or other considerations, like (God forbid!) bounties. It isn't a perfect system though. Whilst all the shichibukai introduced so far were present at the battle, they faced opponents which differed in rank and strength- such as Jinbei facing Akainu compared to Boa Hancock against Smoker, so whether they left the battle unscathed (like Mihawk, Hancock and Doflamingo) compared to the ones which took a fair bit of damage (Crocodile, Moria, even Blackbeard- at the time) is unreliable. Also, that battle featured a few battles between shichibukai which were unaccounted for. Sure, whilst Crocodile couldn't handle Jozu in the same way that Doflamingo could, he seems to have been able to come away from picking fights with both Mihawk and Doflamingo in the same condition with which he started them...though this may have been a creative choice on the part of Oda not to expose the full extent of their powers early on.

I don't know if we can safely rule on Doflamingo being the 'strongest' shichibukai when we still have that mystery 7th member waiting out there. I'd be interested to see if they were also present at Marineford.