So, I plan on making a slow cooker pot roast for dinner tonight, and I pull up a recipe from the internet. The ingredient list contains about what I expect, so I make a shopping list and move onto the instructions.
Season to taste before I start cooking? Who’s supposed to be doing the tasting?
Well, I presume you have at least a vague idea of how much salt and pepper you’d like in the final product, on a scale of “none” to “lots”.
Yeah, if you like lots of salt, add lots, and if you don’t like very much salt, then don’t add very much.
So, in this instance, “season to taste” actually means “season to preference?” They should say that, then.
I’ve always known the word “taste” to have more than one meaning. After all, when someone says “You have great taste in men/women,” they aren’t talking about you eating them. 
But which preference? Gender? Sports team? 
I’ve understood the use of ‘taste’ in that context from the get-go. As in “that’s not to my taste”, etc. YMMV.
That’s exactly what “season to taste” means. “Season to your tastes.” I’ve never parsed it any other way.
What if my tastes go beyond just salt and pepper?
Then add what you like, smart-aleck. 
Then add summer, winter, whatever seasons you want.
Parsley, sage, rosemary, and October 14th at around 3 pm.
What thyme is that?
Lillian Gish’s birthday?
This is a Lillian Gish reference, isn’t it, you sly dog?
(Lillian is VERY much to my taste, and I would like to eat her also, c. 1922, after make-outs)
“season to taste” has been standard for at least a hundred years. Using a new phrase would confuse everyone familiar with cookbooks and recipes.
Okay we get it this recipe writer needs a copy editor.
We’re not speaking since I found out you require mayonnaise on chicken sandwiches. Fie, I say. Feh. Imprecations upon thee.
Oh, and October 14 is also the birth date of Captain Nintendo Dude and NoChillMikey, you old fogey.
I agree with you, that’s a poor direction to put in a recipe. You have no way of knowing how seasoning at the very beginning will taste at the end, season “to taste” would only make sense when the dish is finished or nearly finished.
When I was a kid, I believed (possibly due to Dad’s love of trolling small children) that ‘season to taste’ in recipes meant that, without seasoning, the food didn’t have any taste at all.
If the recipe required a precisely measured amount of seasoning, it would likely have said so. “To taste” means they are leaving it to the cook’s discretion or preference.
Most people who know their way around the kitchen understand that you can adjust seasoning while you cook, up to the very end of the process in many cases.
So add some, not too much, at the start. Cook. Taste. Add more as needed.
It’s in a very large percentage of savory recipes. It’s perfectly understandable to the majority of the intended audience.