Historical clue formulations

• Many an M.I.T. graduate: Abbr. — 2023-08-15
• Part of STEM: Abbr. — 2022-02-27
• Profession for many an M.I.T. grad: Abbr. — 2022-02-14
• Head of a train: Abbr. — 2021-10-26
• Many a graduate of 37-Across: Abbr. — 2021-05-25
• Many an M.I.T. grad: Abbr. — 2020-06-12
• Certain B.S. holder: Abbr. — 2019-12-26
• Many a SpaceX worker: Abbr. — 2016-12-29
• One practicing the "E" of STEM subjects: Abbr. — 2016-06-13
• One who pulls a train whistle: Abbr. — 2015-08-24
• App creator, perhaps: Abbr. — 2015-03-15
• Tech grad: Abbr. — 2015-02-15
• Dam designer: Abbr. — 2014-03-14
• M.I.T. grad, often: Abbr. — 2013-08-27
• 56-Down grad: Abbr. — 2012-10-16
• Applied sci. professional — 2012-10-06
• Many a NASA worker: Abbr. — 2012-07-18
• Many a Lockheed Martin employee: Abbr. — 2011-11-12
• Mech. whiz — 2011-07-21
• Many an M.I.T. grad — 2010-07-18
• Mech. expert — 2010-05-19
• Hwy. planner — 2010-04-27
• Mech. master — 2010-03-12
• Hwy. planner — 2010-01-28
• Bldg. planner — 2009-10-04
• Bridge or tunnel designer: Abbr. — 2009-02-09
• Mechanical whiz: Abbr. — 2009-02-03
• Mech. ___ — 2009-02-01
• Technician: Abbr. — 2009-01-29
• Many an M.I.T. grad: Abbr. — 2007-12-26
• Rd. designer, e.g. — 2007-11-24
• Many a NASA worker: Abbr. — 2007-10-14
• Boeing worker: Abbr. — 2007-06-10
• Bldg. planner — 2007-04-01
• G.E. employee — 2007-03-31
• Hwy. dept. employee — 2006-12-08
• Bldg. planner — 2006-11-19
• Many a NASA employee: Abbr. — 2006-10-29
• M.I.T. grad., often — 2005-10-18
• Many an M.I.T. grad: Abbr. — 2005-03-02
• Bridge builder, e.g.: Abbr. — 2004-08-03
• M.I.T. grad: Abbr. — 2004-06-10
• Techie: Abbr. — 2003-07-06
• Bldg. contractor's hire — 2002-10-06
• Tech sch. grad — 2001-01-31
• R.P.I. grad, perhaps — 2000-06-23
• M.T.A. employee — 2000-03-04
• M.I.T. grad: Abbr. — 1999-09-08
• Technician: Abbr. — 1998-06-10
• M.I.T. grad: Abbr. — 1996-08-29