I fly the NG with FMC version 10.8. My airline uses company routes which is basically origin navaid to destination navaid via airways without SIDS and STARS. Our SOP is to only enter approach and runway in the cruise once clearance is received. Once FMC preflight complete, the FMC indicates TOC n TOD and sets a speed and altitude automatically for the destination navaid.
It's usually something like 165/1375 at ABC. ABC is about 1.4 miles from the runway and aerodrome altitude is 1125' or thereabouts.
You don't need to enter an approach or runway to generate TOC and TOD on any of the 737s I've flown including classics. I remember this because I like to go as high as possible with about 6-8 minutes in the cruise so i check the time at TOC and TOD while still on ground to determine how high to climb.
We mostly get radar vectors so the trick I use is to create a waypoint 25nm from destination navaid and set spd/alt as 240/FL100 which kinda works out to a CDA traffic permitting.