Instant-read thermometers are excellent for their speed of use, reliability, and accuracy — and no, they don’t let any significant quantity of juices out. Regardless, meat naturally leaks juices as they cook, and the amount lost this way is much more than what what’s released from piercing. Instant-read thermometers provide the best way to get in (and out) of your meat with a precise measurement. Opening the hood may free some heat and smoke, but the trade-off here is a snapshot of the accurate temperature without delay.