I've experienced the same. In '08 and '09 I had great years where I netted 11 and 10 cts per 100 shares yet last year it was only 3 cts on 1/2 the volume. Obviously, '08 and '09 were unique years and I'm not confusing brains with a bear market . It's frustrating. The fear will return. It's just a question of when, not if.
It's not a question of how big it is but how much you get to keep. People should trade what works for them.
scalping for pennies. can be good if you have do volume and also have good ecn rebates. it all adds up...but usually depends on the volatility of that stock.
if the market is swiping around and you can get filled you can easily make over 100k just scalping for a few cents at a time.
I trader for pennies, and half pennies when i hit bids and take offers. Hit EDGA with size on a breakdown, buy BATS mid and get a sick rebate plus nice profit. 30,000 shares gets you like 170 after the rebate.
I set the order PEG and peg type to primary. Then under destinations in sterling settings I set up batsmid and batsaliq or smthing like that as mid points. I'm sure you can do it using IB or something. I clear through ECHOtrade.