I wouldn't do this, for a couple reasons: It's not good to spend any amount of time high if it can be avoided. Also if you go quite high, it's harder to accurately correct, and takes a couple more hours.
I would work a bit more to find resources for carbs. You don't have to rely on restaurant information. I don't eat in chain or fast food restaurants, so I always have to figure it out myself. You can find an app on your smartphone or get an old school printed out list of carbs, or check calorieking.com online. Once you have eaten in a certain place and had certain dishes you will get familiar with more accurate carb counts and will even get to the ability to eyeball and accurately bolus.
Bottom line: I would make a good educated guess and then bolus. Then if you are too high or low by a bit you can correct later. I wouldn't just go without mealtime bolus. You'll regret it!
It is almost impossible to have full knowledge about how a meal will affect your blood sugar. So what I do is two things, first I make choices which are low in carbs and "predictable." This means that any errors are greatly reduced. I substitute side dishes and things like that and avoid foods with sauces that may contain hidden stealth carbs. The second thing I do is bolus for the "known" carbs. It may well be that a meal contains more carbs than I think, but it is better to be a little high and correct than to have a hypo.
A meal bolus will always better match your blood sugar profile and be more predictable (than a correction).
I use the "Calorie King" book to get a "ballpark" value for foods eating out. I agree w/ Zoe and BSC that generally, it seems like restaurant foods will have extra, hidden carbs, not to mention the fat/ protein combo that will also produce a delayed and sustained high. If you don't know for sure, or are uncomfortable guessing, it's definitely better from a BG perspective to eat a side salad and have minimal risk of having a big BG mess to clean up?
No, you really DO NOT want to do this. First, if you do this, you will be spending a fair amount of time high, and this causes damage to your body. Second, corrections do not work as well if you are really high.
When eating out, I do several things. First, I try to eat at places where I have had experience with the food and how it is prepared. Sometimes, I will eat at a place 2-3 times and slowly figure out how much bolus is needed for a certain dish (an educated trial-and-error process). Second, if eating somewhere unfamiliar, I stay away from carb-heavy dishes and opt for things that I know are low carb. I avoid sauces and glazes, as these obviously have a lot of sugar in them. I stay away from all bread, rice, and pasta.
I usually try to estimate my carb intake as best I can using an app on my phone (CarbFinder). If I'm eating at a chain restaurant, I can usually find the nutritional info online.
Finally, when I do bolus and am just totally uncertain about the amount, I will generally underbolus a bit, knowing I will probably have to correct a bit later on. BUT, this is less harmful than not bolusing at all, and I rarely go over 220 or so.
I actually almost always eat bread at good restaurants. Using 50% of gross weight for the carbs is usually pretty close but then I also bring a scale to weigh the bread and often have an apple in my pocket for dessert. Using those building blocks, I can focus on the protein and green vegetables and usually come pretty close.
I use a small Dymo digital postal scale that I picked up at Staples. It's about 6" square - a little bigger than a copy of Calorie King - and can handle a couple of pounds.
Far better to dose for an educated guess of carbs. If necessary lowball it and correct later.
We never have complete information about anything in life, but must continue living nevertheless :-).