TA is difficult in Europe and often also related to weather conditions, as you can easily get from listening to ATIS of several stations
Chickenhouse, you're talking rubbish again.
TA is not a function of weather conditions, and rarely given on ATIS.
Even further, if they give you 5.000ft on QNH 1020 and your local pressure level is more 950 - go for the 1020
What the **** are you smoking old boy? Does your googling suggest there's some strange "pressure level" instrument in a cockpit, or that pilots are determing QNH for themselves? Or that there's a 70 hectopascal variation in QNH at the same time over the same continent (unless there's a hurricane going on somewhere nearby, in which case there are bigger issues to worry about than cleared altitude).
do not think on your own
Indeed.
G