The team at gov.uk is doing an excellent job regarding web performance, credit where credit is due. In many ways role model behavior.
Still, the results are such a stretch as to not have that much meaning. They have to descent all the way to 2G to see any meaningful difference, and I'm assuming they are cold visits (typical in lab-based testing).
For those exceptional users, this creates a difference from very poor (12 seconds) to still poor (9 seconds). Probably less because they'd normally have a warmed up cache.
Is it empathetic to improve performance for those users? Very much yes, do it as far as you budget allows for. But as it comes to jQuery specifically, the conclusion is that its negative impact is negligible.
Still, the results are such a stretch as to not have that much meaning. They have to descent all the way to 2G to see any meaningful difference, and I'm assuming they are cold visits (typical in lab-based testing).
For those exceptional users, this creates a difference from very poor (12 seconds) to still poor (9 seconds). Probably less because they'd normally have a warmed up cache.
Is it empathetic to improve performance for those users? Very much yes, do it as far as you budget allows for. But as it comes to jQuery specifically, the conclusion is that its negative impact is negligible.