教材原文如下：
Long-only investing, particularly strategies that focus on large-cap stocks, generally offers greater investment capacity than other approaches. For example, the MSCI ACWI has a total market cap of nearly $37 trillion, and the 10 largest companies are worth $3.4 trillion.42 For large institutional investors, such as pension plans, there are no effective capacity constraints in terms of the total market cap available for long-only large-cap investing. Long-only strategies may face capacity constraints, however, if they focus on smaller and illiquid stocks or employ a strategy reliant on a high level of portfolio turnover. Unlike long-only strategies, the capacity of short-selling strategies is limited by the availability of securities to borrow.
(Institute 505)
这段说long-only 有greater investment capacity focus on large cap stocks，原因似乎是说long only 在投资规模上没有限制？而long-short受限于股票的借入，但是大盘股不是应该更好借入么，反而小盘股流动性差的股票应该更难借入，从这个角度讲long only应该是在focus small cap stock时才有greater investment capacity啊？
请解释一下教材这段话和以上问题，谢谢！
