Zack Thomas wasn't ranked an Elite LB, he was drafted in like the 6th Round by Miami, what did he do?
He only went on to be one the Top 5 MLBs in the NFL during his time. Nowadays he's on the downside and playing for the Cowboys. But when he was younger, he was an absolute animal on the field.
He didn't have the size, he didnt have the strength, but he had the SMARTS and WORK ETHIC which made him one of the most instictive MLBs.