The best thing you can do for summer practice, in your case, is just go and work on mechanics. Work on your approach, armswing, timing, release, accuracy, ect. Anything that you had trouble with during the league. A lot of houses don't really bother putting out much of a shot during the summer simply because its not economical to do. So don't worry about what your scores are, if you hit the pocket, if you left a lot of ringing 10s and such if you know the lanes are crap....just work on things and feel a good shot coming off your hand.
I run into the same problem. The house I bowl a summer league in has like 1 or 2 leagues all week....so they oil once and thats it. Its hit and miss when I go to practice, so I just work on something or several things that I felt I wasn't doing well during the league night. Combine that with the fact that the house offers $.50/game of open bowling to league bowlers during the summer.
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University at Albany 2007
-Let's Go Danes-
ROTO GRIP - King of Them All
STORM - The Bowlers Company
Harry E. Inglis 3/31/1915 - 2/3/2009