To me, engines should be tech'd inside a tech barn. Less dirt and moisture blowing around to contaminate the parts.
Also less opportunity for a crowd to watch. Not that I'd expect any of then to get a good enough look to be able to really learn anything, but because we don't need them making comments and trying to sway the results. That and claiming they "saw" or "heard" something they didn't actually see or hear.
To me, the only people who need to be present is the tech crew. If the tech man doesn't have a helper, then he might allow the engine's owner to help him. I don't care that somebody paid for the protest - they paid to hear the results, which they will get when the tech is done. They didn't pay for an engine building lesson. If you want an engine building lesson, buy a fresh engine from that builder and then tear it down and learn for yourself.
I like to trust the tech man, otherwise what's the point? If I can't trust him I shouldn't be racing there, or at least not participating in that track's protest procedure. And yes, I've seen untrustworthy tech men. Had one test fuel by following WKA procedures - including a clean graduated beaker - for the race winner, while using a used water bottle (even still said "Dasani" on it) and that you could see still had water droplets in it for the second and third place karts "to save time"... and (surprise!) find the winner's fuel legal while finding second and third place's fuel illegal due to water content... (surprise!) the winner was a good buddy of the track owner, who hadn't collected enough money to meet the advertised payout... yeah that was the last time we ever raced there, and the track has now closed.
I'm also not a fan of the rule that if you're protested that you have to pay an "acceptance fee". After paying entry fees and buying the required fuel at the track and some dinner I usually don't have enough cash to cover that "acceptance fee". I've had better financed teams take advantage of that (protesting me knowing that I cannot pay to accept, so they get my payout and points). If I do have the cash and accept the protest I end up with a box of dirtied parts and torn up gaskets etc. that my winnings are not going to pay for. Been told that this "acceptance fee" cuts down on vindictive protests, but as the victim of the protest I don't see how I was "vindictive". But if that's the track rules and how it wants to run, fine... I won't run for points there (meaning don't expect me to be a regular).