Macy’s warned yesterday that its stores were awash with merchandise after a sluggish fall season and that slow business would force it to go all-out on discounts during the holidays, the New York Times reported today. Aggressive discounting from one of the country’s biggest merchants is bad news for retailers this holiday sales season, which is shaping up to be highly discount-driven. It also raises questions about the strength of the economic recovery, and of consumer sentiment. But a shift in the way Americans shop because of the proliferation of e-commerce, and the power to compare prices at a click of the mouse, has meant that a brightening economy is no longer a tide that raises all retailers, said Oliver Chen, a retail analyst at Cowen.