Is Investment Banking a Good Business Model?

I don't think investment banking will be a good business because I don't think they can use as much leverage as they used to. A lot of investment banking money in my view was made through applying very high leverage to very safe in efficiencies in the market. So, without huge amounts of leverage, I don't know that investment banking makes investment banks are very attractive. Has cash tag Jeff ever invested in any thrift slash mutual bank conversions? If so, did he do well with them? Does he have any interesting stories, thoughts and or advice about them? No, I have not. Let's see. What are some good books to read to learn more about banking and analyzing banks