I was thinking about Sielshegh gems today (oddly enough) and was wondering, if a scion had his bloodline boosted from a sielsegh gem while he was busy concieving a child, shouldn't the upwardly adjusted bloodline be the score to be averaged? After all, they effectively have an empowered line.

To illustrate our point using an entirely fictitious character.
Tom Brady, a human male with an INT and CHA of 3 each is (clearly) a chaotic evil scion of Azrai with a bloodline strength of 20.

He puts on the funny jester hat with a series of sielshegh gems keyed to azrai that boosts his Bloodline by 50 points. He now has an effective bloodline of 70 while remaining in contact with the gem.

Tom that evening gets busy with his girlfriend, a scion 10 of Azrai while wearing his jester hat. A child is concieved.

Typically that child should have a bloodline score that averages the score of his parents. Tom's unmodified score of 20 and his girlfriend's score of 10 should result in a child with a score of 15. However since his bloodline is enhanced by the gems, why WOULDN'T his score of 70 be the value used for determining his average?
It seems to break the system. The Roele's could wear their funny state crown hat to bed to effectively empower each generation with a greater bloodline than the preceding generation.