If last week's rally felt different than the late September/early October rally, it is because it was. Take a look at the McClellan Summation Index and notice how quick it was to get off the mark and move upward in that early October rally.
It took a few days for the Summation Index to engage in the late September/early October rally, but it also took the S&P some time to engage, as well. But once it engaged breadth was in gear using this indicator.
Now look at last week's rally on the chart. It took one week for the S&P to cover the ground that it took three weeks to cover back then, and the Summation Index has barely lifted itself. That tells me last week's rally was index-led for the most part.
Or, take a look at the 10-day moving average of stocks making new lows on Nasdaq. Look how fast it plunged in early October. Last week it barely budged. It ought to head down this week. Will it?
Now take a look at my own Overbought/Oversold Oscillator. All it did last week was get to the zero-line -- and is now back under it. Remember, this is not based on price, but on breadth.
This is why I note that last week's rally felt very concentrated in the index-moving names.
Do you know what had no problem moving last week? Sentiment. One week ago, we looked at the chart of the equity put/call ratio, because it had tagged .77 (green arrow), which was the highest reading since May. On Friday, it chimed in at .41 (red arrow). Folks spent the week refusing to join the party, but by Friday they could take it no more and dived right in.
I noted on Friday that I thought we could see us back off a bit and rally again, and I still believe that to be the case. The Oscillator above should rise handily this week (it's the math) as it works its way to an overbought reading mid-to-late in the week. So we could get to a short-term maximum overbought condition, with too bullish sentiment, later this week.
But take another look at the equity put/call ratio chart. Do you see the way the last two short-term peaks in the S&P (black line) needed two such low readings (blue circles) before it was clear the sentiment had shifted?
We know sentiment has shifted. After all, my Saturday Twitter Poll showed the folks looking for more upside at 55%, while those looking for more downside were at 45%. We had a similar reading in mid October; recall last week it was tilted to folks looking for more downside.
Just to go back to the 2016 post election time frame, and notice that it took an entire month before we saw a reading for the put/call ratio under .50. I maintain this post election time frame looks quite different than that one did.