It is true that small businesses cannot borrow and lend with equal ease at the quoted market interest rates. Moreover, even small businesses can usually easily implicitly lend by repaying some of their debt, so they aren't nearly as constrained as one might think. I think you are confusing market-clearing interest rates and natural interest rates. Of course, lenders have no choice but to lend at the lower rate if the central bank cuts its rates. But at my remarks to Vince indicate, there is no reason for long-term interest rates to be deceptive or cause malinvestment.
Arbitrage prevents it.
Thus, my view of business operations bears no relation to the story you tell. If rates are low now, but will be higher later, I wouldn't tell my boss not to lend. I would suggest lending short, so we could take advantage of higher rates once they hit. I would however get fired if I presented an analysis of a project's profitability, and in my calculations I stupidly used currently low short-term rates to discount all future cash flows. One way that real wages can be rigid is if it takes time for them to change.