E61 Grouphead Digital Thermometer Adaptor

An honest question, not an antagonistic one as you mention temperatures at the puck but I did not spot that the probe is measuring at the puck.

If I understand correctly then provided there is little temperature difference by the time water reaches the puck it's a really useful device. If, however the temperature varies enormously (or inconsistently) then it may be misleading and unreliable. What do you think?

Coffeetime