MBank's president acknowledged that the lender's plans to serve an emerging market may have been a bit overambitious. Jef Baker confirmed that the Gresham-based bank has pulled back on plans to offer accounts to Colorado marijuana companies, but not for the reasons some have surmised. "We wanted to try and serve that market because the need is so strong there," Baker told Adam Worcester, a Portland Business Journal freelancer. "We effectively bit off more than we could chew. The scope, size, magnitude…