AAvsKK

I always assumed it was randomly generated, it would be interesting to see some stats from a sample size that makes a normal distrubtion meaningful. Is it possible Jagex lets the number of people with the level to assist a particular skill influence the frequency the skill is required to level up an effigy?

I completely forgot about assisting...

It looks that way. If you managed to get another 23 lamps from slayer etc and used them when you hit 98 rc you'd skip that level and be wearing a shiny new rc cape right away (and would have gained an extra 283k xp rather than if you'd used them at 90).

Isn't using them at 98 the most efficient? As far as I know there isn't any increase in xp/hr between 90 and 99 in rc. Xp gained from lamps: 90 = 36090xp, 98 = 46589xp... a difference of 10499. If you had 10 in the bank for example that would be over 100k worth of xp you'd be throwing away if you used them at 90 rather than 98. How many do you have?

You answered your own question. You can't make a profit when the outcome is 50/50. Anyone who says you can is subscribing to what's known as gambler's fallacy. The majority of these people are losing gamblers, the rest are lucky. They don't understand probablity and favour superstition, emotion and incorrectly applied math over real statistics and common sense... see below: This is an example of gambler's fallacy. Now what if we take the eleven game winning streak but change it to a losing streak? Then, what if we apply the infamous Martingale System? Suddenly we find ourselves facing a whopping 10240M bet for the original 10m return.