Is it worth eating there before the show?
It's ok; fairly middle of the road; nothing to write home to Japan about. Nice setting--can sit Japanese style on mats. Convenient before a show. How about Le Cheval several blocks away in downtown Oakland for Vietnamese food? Very good and very cheap. Or Soizic is walking distance from Yoshi's--3rd and Broadway. Looks like nothing from the outside; very nice inside.
I agree with these choices - Yoshi's very ordinary and expensive --- check out Everett and Jones on B'way and 1st --- top of the line BBQ -- they feature blues bands over the weekend ---- ribs, chicken, links, etc. yumm - the beans are great. After Yoshi go to Bluesville - B'way and 1st --- great blues dance club -I saw Muddy Water's son last week - way cool!! and great mixed crowd.