I putt a lot with my wedge, and would usually plan on leaving out the putter in favor of another club. But the lag putting problem is very real. From a foot out to about six or eight feet, I can really putt with my wedge. In fact I have set up my putters with the length and lie of a wedge--35" and 62*.
I have tried putting the longer ones with a hybrid or driver, but I'm not so good with them
My brother once played in a two-man scramble where each guy got three clubs and you couldn't share. He took a driver, seven iron and L wedge (it was a Pete Dye course), and managed to go make two birdies and an eagle in a three-hole stretch without his partner contributing.
Ken Moum