+1

With 2 riders a rule of thumb is that each rider should do about 30 second pulls, minimum, and closer to a minute, to give the other rider a chance to recover. You may want to reduce the length of the pull of the weaker rider to 15 seconds or so (20 revolutions?) and have the stronger rider do a minute or so. The key here is the recovery of the weaker rider - if the weaker rider can recover enough to pull at the agreed upon speed/effort then you're all good. If the weaker rider can't pull then the other rider needs to pull more. If the other rider needs to pull less because they're getting too fatigued then the two need to slow down.

When Greg Lemond led the Junior National Team to a bronze medal in the 70km Junior World Team Time Trial Championships he was by far the superior rider (Ron Kiefel, Greg Demegen, and one other rider was on the team). One rider crashed early on, leaving 3 riders (and the time is taken off the 3rd rider so the remaining riders had to finish). Another rider was unable to pull so sat at the back. One rider took about 30 second pulls. Lemond took 2-3 minute pulls and basically did the TTT by himself. I've never seen an article saying who crashed and who couldn't pull so I don't know that info. The TTT bronze against other countries' specialists, combined with his surprise silver on the track against a specialist (he'd raced on the track for something like 14 minutes in total before the Worlds), and the surprise gold (flat course, expected to be a big sprint, but he powered a two man break clear of the field to win the gold), marked him as a rider of the future.