Marcus Williams is one BAD dude! Best Safety in NFL

To me, this is like saying, I don't want Deion Sanders on my team; let's face it, he couldn't tackle a 5 year old.

Honestly, I'd take 6 Marcus William's in the back field...nobody would complete a pass on us. 3rd in INTs for Safety since he's been in the league.
Apples to oranges. Open field tackles and tackles in coverage are entirely different beasts. Sanders would be in a receiver's hip pocket more often than not and even if he surrendered a catch, all he'd have to do is swipe and the receiver's legs and make a tackle. Williams has to cover a lot of ground and then make open field tackles.

Honestly, I'd be far less critical if he was wrapping opponents up and his tackles were just getting broken than entirely whiffing which just shows poor technique when the receiver wasn't even trying to make him miss.

Oddly enough the situation reminds me of Jenkins' first stint here, except his problems weren't with tackling, it was piss poor pursuit angles leading to big plays. He was a good player, but he'd take these horrible angles in pursuit of the ball carrier and they'd nearly always get the edge. That being said, Marcus Williams is a great FS.