Because his strategy would be perceived as inaction, people greatly underrated his bravery.Whilst having totally different racing tactics to Contador, Gerrans probably had very similar philosophy.
"The second place is no good."
Hence he always raced as if he cared less about a podium then his group 1 riding companions, calling their bluff; "I don't care if those 5/10/20/50 riders in group 2 catch us, but I know that you, so keep working, thanks."
Gerrans was not as good as Matthews imo, but he has a better palmares.