Significant speedup #3120

Job	Run time
ubuntu-clang-deprecated Debug	21m 2s
ubuntu-clang-deprecated Release	23m 15s
ubuntu-clang-quaternions Debug	22m 15s
ubuntu-clang-quaternions Release	22m 54s
ubuntu-clang-tbb Debug	23m 20s
ubuntu-clang-tbb Release	25m 4s
ubuntu-clang-cayleymap Debug	22m 21s
ubuntu-clang-cayleymap Release	22m 33s
ubuntu-clang-system-libs Debug	21m 12s
ubuntu-clang-system-libs Release	22m 50s
ubuntu-no-boost Debug	21m 7s
ubuntu-no-boost Release	22m 28s
ubuntu-no-unstable Debug	17m 47s
ubuntu-no-unstable Release	18m 41s
	5h 6m 49s

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