In SERVER-13391, the slow1 and slow2 suites were split off from the noPassthrough and noPassthroughWithMongod suites in order to reduce the execution time of these suites.

Now that resmoke runs all tests for these suites in parallel, it is in theory no longer necessary to maintain separate slow1/slow2 suites, as the amount of time needed to execute a full suite is dominated by the amount of time taken to run its longest test.

This hypothesis should be verified (namely, that moving the tests from the slow1/slow2 suites back into the "no passthrough" suites does not increase the amount of time needed for a full build), and slow1/slow2 should be dismantled if it holds true.