I think there is no use to master bash, sed and awk. When you have a task that becomes tricky (beyond entry level) in sed, it is often easy in awk. When you have a task that becomes tricky in bash or awk, switch to a more powerful scripting language like perl/python/ruby/?. I love perl, but I feel it is getting outdated. I try to improve my programming speed in python but I am still far from my speed in perl.