Sorry to sound like the 'Voice of Doooom'. That was not my intention. You are right on the money when you say that the dump can be almost instant.
A couple of things I've learned over the years:
a) The smaller the boat is, the quicker the motion, (directly related to point b)
b) The stronger the wind is, the more amplified the motion tends to be, especially in gusty conditions.
I live and sail on the 'protected part' of the beginning of the 'Inside Passage' of Vancouver Island, BC, Canada. However, it can get very harsh here, due to living in a set of crosswinds that develop due to mountainous territories. One day it's becalmed, the next day, not so much; however if a front moves through from the north west, it's an Arctic Front (onshore), if it's from the south east (protected parallel to the shoreline), it's a 'Pineapple Express' that started out in Hawaii. In other words, it's a crap shoot unless one reads the sat weather map and checks the VHF Weather Channels. Each set of winds has their own set of pros and cons. If the wind comes from behind me (rarely) it can create a mess due to a venturi blasting through the mountains of Vancouver Island.
You will find that the time you simply sit on the beach from where you sail can give you tremendous insight on the local winds in 'usual conditions'.
As I enjoy solo sailing in one of the most amazing cruising regions on this Planet, due precautions have to be taken. The point I mentioned about using a bungie tied to your tiller bar can be done by simply attaching a light bungie cord in one direction only. This puts a slight (one way) pressure on your helm but if you let go of the steering, the boat has no choice but to sail in circles. (This needs to be adjusted depending on the strength of the wind or it will be useless as the boat will zig-zag as a result)). Experiment to get the right tension, if you wish. Having ready access to the Main sheet at all times is of course a must.
Other considerations are the standard safety gear needed if you want to venture beyond a given point that you have never been to before in open water. As the average ocean temp here is about 54 degrees, a PFD will not save you from hypothermia unless one is close to shore. Your water temp will prolly differ where you sail, but certain lakes if they are mountain fed can be incredibly chilly. Even in the Summer here, I wear a wetsuit simply just in case I get dumped.
My suggestion of wearing a lifeline did cause me some concern as also Augaug mentioned that you can get entangled, unless you are aware of the limitations of using one at all times when going solo well from shore (practise makes perfect). It's just another line that one needs to be aware of if you choose to use one.
Considering that I may sound like a worry wart, not so. Yes, I do have a lot of fun sailing here. I've been doing it for a lot of years with amazing memories.