Ok, good to know, though I can't really see a practical situation where it would come up, since basically all fleets have at least one frigate with max burn of 10. So maybe it's okay if it stays hidden, since the player can't really use it to his or her advantage... Bar doing something silly like having a Tempest-only fleet Wink
You could install Augmented Drive Field to all of your burn 10 ships, that would make it work (not against Tri-Tach or Lion's Guard as they near always have Tempest's.
The other thing you could possibly do is engage, hunt down and kill each of those burn 10 frigates, and then escape the larger ships.
Fortunately, many civilian frigates that are less likely to be deployed in an engagement (like the Dram, Mercury, Hermes, and Shepherd) are burn 9.
(This is indeed fairly deep in hidden mechanic territory. I really ought to clean this all up at some point.)
One thing I could see to make this more transparent would be a "abandon your slower ships in order to disengage cleanly" option. But you'd have to make sure it has a confirmation screen with "These ships are who you're leaving behind. Are you sure?" and possibly an extra "Are you really sure?"